Nat  Kutch

Nat Kutch

1598609880

Pleasure and Business Merge

It used to be that when someone heard the term “drone” the first thing they thought of was militaries flying unmanned aerial vehicles (UAV) over hostile territory to record valuable information or potentially even deploy weapons. With the advent of recreational drones, the focus has shifted, with many associating drones with fun, outdoor activities.

Now, with significant increase in the consumer and commercial drone markets, there’s an entirely new set of potential implementations for the technology and the people utilizing it.

North America Consumer Drone Market By Technology, 2012–2022 (USD Million)

_Consumer Drone Market Analysis By Product, _Grand View Research

The market for consumer drones has been growing consistently over recent years, especially after the Federal Aviation Administration (FAA) in the US was brought to court in response to an original decision requiring recreational owners to register their drones. Upon review, a federal appeals court deemed the program unlawful and stated that recreational drone users would not need to register their drones. Now, a recent bill from the Trump administration requires owners to register, yet again. However, even with the on-again, off-again relationship with the FAA, drone enthusiasts are still involved in their hobby in large numbers. In 2016 it was reported that drone sales tripled in one year alone, according to research from The NPD Group. Ben Arnold, executive director and industry analyst for The NPD Group said in a statement along with the published research that the growth can be attributed to many new uses for drones.

#data visualization

What is GEEK

Buddha Community

Pleasure and Business Merge
Carmen  Grimes

Carmen Grimes

1595491178

Best Electric Bikes and Scooters for Rental Business or Campus Facility

The electric scooter revolution has caught on super-fast taking many cities across the globe by storm. eScooters, a renovated version of old-school scooters now turned into electric vehicles are an environmentally friendly solution to current on-demand commute problems. They work on engines, like cars, enabling short traveling distances without hassle. The result is that these groundbreaking electric machines can now provide faster transport for less — cheaper than Uber and faster than Metro.

Since they are durable, fast, easy to operate and maintain, and are more convenient to park compared to four-wheelers, the eScooters trend has and continues to spike interest as a promising growth area. Several companies and universities are increasingly setting up shop to provide eScooter services realizing a would-be profitable business model and a ready customer base that is university students or residents in need of faster and cheap travel going about their business in school, town, and other surrounding areas.

Electric Scooters Trends and Statistics

In many countries including the U.S., Canada, Mexico, U.K., Germany, France, China, Japan, India, Brazil and Mexico and more, a growing number of eScooter users both locals and tourists can now be seen effortlessly passing lines of drivers stuck in the endless and unmoving traffic.

A recent report by McKinsey revealed that the E-Scooter industry will be worth― $200 billion to $300 billion in the United States, $100 billion to $150 billion in Europe, and $30 billion to $50 billion in China in 2030. The e-Scooter revenue model will also spike and is projected to rise by more than 20% amounting to approximately $5 billion.

And, with a necessity to move people away from high carbon prints, traffic and congestion issues brought about by car-centric transport systems in cities, more and more city planners are developing more bike/scooter lanes and adopting zero-emission plans. This is the force behind the booming electric scooter market and the numbers will only go higher and higher.

Companies that have taken advantage of the growing eScooter trend develop an appthat allows them to provide efficient eScooter services. Such an app enables them to be able to locate bike pick-up and drop points through fully integrated google maps.

List of Best Electric Bikes for Rental Business or Campus Facility 2020:

It’s clear that e scooters will increasingly become more common and the e-scooter business model will continue to grab the attention of manufacturers, investors, entrepreneurs. All this should go ahead with a quest to know what are some of the best electric bikes in the market especially for anyone who would want to get started in the electric bikes/scooters rental business.

We have done a comprehensive list of the best electric bikes! Each bike has been reviewed in depth and includes a full list of specs and a photo.

Billy eBike

mobile-best-electric-bikes-scooters https://www.kickstarter.com/projects/enkicycles/billy-were-redefining-joyrides

To start us off is the Billy eBike, a powerful go-anywhere urban electric bike that’s specially designed to offer an exciting ride like no other whether you want to ride to the grocery store, cafe, work or school. The Billy eBike comes in 4 color options – Billy Blue, Polished aluminium, Artic white, and Stealth black.

Price: $2490

Available countries

Available in the USA, Europe, Asia, South Africa and Australia.This item ships from the USA. Buyers are therefore responsible for any taxes and/or customs duties incurred once it arrives in your country.

Features

  • Control – Ride with confidence with our ultra-wide BMX bars and a hyper-responsive twist throttle.
  • Stealth- Ride like a ninja with our Gates carbon drive that’s as smooth as butter and maintenance-free.
  • Drive – Ride further with our high torque fat bike motor, giving a better climbing performance.
  • Accelerate – Ride quicker with our 20-inch lightweight cutout rims for improved acceleration.
  • Customize – Ride your own way with 5 levels of power control. Each level determines power and speed.
  • Flickable – Ride harder with our BMX /MotoX inspired geometry and lightweight aluminum package

Specifications

  • Maximum speed: 20 mph (32 km/h)
  • Range per charge: 41 miles (66 km)
  • Maximum Power: 500W
  • Motor type: Fat Bike Motor: Bafang RM G060.500.DC
  • Load capacity: 300lbs (136kg)
  • Battery type: 13.6Ah Samsung lithium-ion,
  • Battery capacity: On/off-bike charging available
  • Weight: w/o batt. 48.5lbs (22kg), w/ batt. 54lbs (24.5kg)
  • Front Suspension: Fully adjustable air shock, preload/compression damping /lockout
  • Rear Suspension: spring, preload adjustment
  • Built-in GPS

Why Should You Buy This?

  • Riding fun and excitement
  • Better climbing ability and faster acceleration.
  • Ride with confidence
  • Billy folds for convenient storage and transportation.
  • Shorty levers connect to disc brakes ensuring you stop on a dime
  • belt drives are maintenance-free and clean (no oil or lubrication needed)

**Who Should Ride Billy? **

Both new and experienced riders

**Where to Buy? **Local distributors or ships from the USA.

Genze 200 series e-Bike

genze-best-electric-bikes-scooters https://www.genze.com/fleet/

Featuring a sleek and lightweight aluminum frame design, the 200-Series ebike takes your riding experience to greater heights. Available in both black and white this ebike comes with a connected app, which allows you to plan activities, map distances and routes while also allowing connections with fellow riders.

Price: $2099.00

Available countries

The Genze 200 series e-Bike is available at GenZe retail locations across the U.S or online via GenZe.com website. Customers from outside the US can ship the product while incurring the relevant charges.

Features

  • 2 Frame Options
  • 2 Sizes
  • Integrated/Removable Battery
  • Throttle and Pedal Assist Ride Modes
  • Integrated LCD Display
  • Connected App
  • 24 month warranty
  • GPS navigation
  • Bluetooth connectivity

Specifications

  • Maximum speed: 20 mph with throttle
  • Range per charge: 15-18 miles w/ throttle and 30-50 miles w/ pedal assist
  • Charging time: 3.5 hours
  • Motor type: Brushless Rear Hub Motor
  • Gears: Microshift Thumb Shifter
  • Battery type: Removable Samsung 36V, 9.6AH Li-Ion battery pack
  • Battery capacity: 36V and 350 Wh
  • Weight: 46 pounds
  • Derailleur: 8-speed Shimano
  • Brakes: Dual classic
  • Wheels: 26 x 20 inches
  • Frame: 16, and 18 inches
  • Operating Mode: Analog mode 5 levels of Pedal Assist Thrott­le Mode

Norco from eBikestore

norco-best-electric-bikes-scooters https://ebikestore.com/shop/norco-vlt-s2/

The Norco VLT S2 is a front suspension e-Bike with solid components alongside the reliable Bosch Performance Line Power systems that offer precise pedal assistance during any riding situation.

Price: $2,699.00

Available countries

This item is available via the various Norco bikes international distributors.

Features

  • VLT aluminum frame- for stiffness and wheel security.
  • Bosch e-bike system – for their reliability and performance.
  • E-bike components – for added durability.
  • Hydraulic disc brakes – offer riders more stopping power for safety and control at higher speeds.
  • Practical design features – to add convenience and versatility.

Specifications

  • Maximum speed: KMC X9 9spd
  • Motor type: Bosch Active Line
  • Gears: Shimano Altus RD-M2000, SGS, 9 Speed
  • Battery type: Power Pack 400
  • Battery capacity: 396Wh
  • Suspension: SR Suntour suspension fork
  • Frame: Norco VLT, Aluminum, 12x142mm TA Dropouts

Bodo EV

bodo-best-electric-bikes-scootershttp://www.bodoevs.com/bodoev/products_show.asp?product_id=13

Manufactured by Bodo Vehicle Group Limited, the Bodo EV is specially designed for strong power and extraordinary long service to facilitate super amazing rides. The Bodo Vehicle Company is a striking top in electric vehicles brand field in China and across the globe. Their Bodo EV will no doubt provide your riders with high-level riding satisfaction owing to its high-quality design, strength, breaking stability and speed.

Price: $799

Available countries

This item ships from China with buyers bearing the shipping costs and other variables prior to delivery.

Features

  • Reliable
  • Environment friendly
  • Comfortable riding
  • Fashionable
  • Economical
  • Durable – long service life
  • Braking stability
  • LED lighting technology

Specifications

  • Maximum speed: 45km/h
  • Range per charge: 50km per person
  • Charging time: 8 hours
  • Maximum Power: 3000W
  • Motor type: Brushless DC Motor
  • Load capacity: 100kg
  • Battery type: Lead-acid battery
  • Battery capacity: 60V 20AH
  • Weight: w/o battery 47kg

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Carmen  Grimes

Carmen Grimes

1595494844

How to start an electric scooter facility/fleet in a university campus/IT park

Are you leading an organization that has a large campus, e.g., a large university? You are probably thinking of introducing an electric scooter/bicycle fleet on the campus, and why wouldn’t you?

Introducing micro-mobility in your campus with the help of such a fleet would help the people on the campus significantly. People would save money since they don’t need to use a car for a short distance. Your campus will see a drastic reduction in congestion, moreover, its carbon footprint will reduce.

Micro-mobility is relatively new though and you would need help. You would need to select an appropriate fleet of vehicles. The people on your campus would need to find electric scooters or electric bikes for commuting, and you need to provide a solution for this.

To be more specific, you need a short-term electric bike rental app. With such an app, you will be able to easily offer micro-mobility to the people on the campus. We at Devathon have built Autorent exactly for this.

What does Autorent do and how can it help you? How does it enable you to introduce micro-mobility on your campus? We explain these in this article, however, we will touch upon a few basics first.

Micro-mobility: What it is

micro-mobility

You are probably thinking about micro-mobility relatively recently, aren’t you? A few relevant insights about it could help you to better appreciate its importance.

Micro-mobility is a new trend in transportation, and it uses vehicles that are considerably smaller than cars. Electric scooters (e-scooters) and electric bikes (e-bikes) are the most popular forms of micro-mobility, however, there are also e-unicycles and e-skateboards.

You might have already seen e-scooters, which are kick scooters that come with a motor. Thanks to its motor, an e-scooter can achieve a speed of up to 20 km/h. On the other hand, e-bikes are popular in China and Japan, and they come with a motor, and you can reach a speed of 40 km/h.

You obviously can’t use these vehicles for very long commutes, however, what if you need to travel a short distance? Even if you have a reasonable public transport facility in the city, it might not cover the route you need to take. Take the example of a large university campus. Such a campus is often at a considerable distance from the central business district of the city where it’s located. While public transport facilities may serve the central business district, they wouldn’t serve this large campus. Currently, many people drive their cars even for short distances.

As you know, that brings its own set of challenges. Vehicular traffic adds significantly to pollution, moreover, finding a parking spot can be hard in crowded urban districts.

Well, you can reduce your carbon footprint if you use an electric car. However, electric cars are still new, and many countries are still building the necessary infrastructure for them. Your large campus might not have the necessary infrastructure for them either. Presently, electric cars don’t represent a viable option in most geographies.

As a result, you need to buy and maintain a car even if your commute is short. In addition to dealing with parking problems, you need to spend significantly on your car.

All of these factors have combined to make people sit up and think seriously about cars. Many people are now seriously considering whether a car is really the best option even if they have to commute only a short distance.

This is where micro-mobility enters the picture. When you commute a short distance regularly, e-scooters or e-bikes are viable options. You limit your carbon footprints and you cut costs!

Businesses have seen this shift in thinking, and e-scooter companies like Lime and Bird have entered this field in a big way. They let you rent e-scooters by the minute. On the other hand, start-ups like Jump and Lyft have entered the e-bike market.

Think of your campus now! The people there might need to travel short distances within the campus, and e-scooters can really help them.

How micro-mobility can benefit you

benefits-micromobility

What advantages can you get from micro-mobility? Let’s take a deeper look into this question.

Micro-mobility can offer several advantages to the people on your campus, e.g.:

  • Affordability: Shared e-scooters are cheaper than other mass transportation options. Remember that the people on your campus will use them on a shared basis, and they will pay for their short commutes only. Well, depending on your operating model, you might even let them use shared e-scooters or e-bikes for free!
  • Convenience: Users don’t need to worry about finding parking spots for shared e-scooters since these are small. They can easily travel from point A to point B on your campus with the help of these e-scooters.
  • Environmentally sustainable: Shared e-scooters reduce the carbon footprint, moreover, they decongest the roads. Statistics from the pilot programs in cities like Portland and Denver showimpressive gains around this key aspect.
  • Safety: This one’s obvious, isn’t it? When people on your campus use small e-scooters or e-bikes instead of cars, the problem of overspeeding will disappear. you will see fewer accidents.

#android app #autorent #ios app #mobile app development #app like bird #app like bounce #app like lime #autorent #bird scooter business model #bird scooter rental #bird scooter rental cost #bird scooter rental price #clone app like bird #clone app like bounce #clone app like lime #electric rental scooters #electric scooter company #electric scooter rental business #how do you start a moped #how to start a moped #how to start a scooter rental business #how to start an electric company #how to start electric scooterrental business #lime scooter business model #scooter franchise #scooter rental business #scooter rental business for sale #scooter rental business insurance #scooters franchise cost #white label app like bird #white label app like bounce #white label app like lime

Why Business Cards Printing are essential for your business

No matter how technological advancement helps in communication but business card printing still worth it. Most businesses prefer to have and share business cards to develop a direct relationship with the potential market. It is an important part of the promotional and branding strategy and effectively described the brand’s nature. It gives ease in sharing the business-related information in the public like at conference, workshops and other.

This is image title

Moreover, a quality visiting card printing online provides the impression of products or services. According to the random research, it is stated that most of the customers draw the conclusion about the business and its products from the card quality or its printing. So, a smart business card with the right size and content is essential for the business.

Here are the factors that will help to understand the importance of the business card in the brand promotion or more:

Provide Contact Details:

One of the main reasons behind business card printing is the contact sharing features. The card contains contact details, name, logo, and other related information that helps the client to reach the business. Further, it helps to describe the brand or product nature before approaching the product or services. Other than the technology usage or sharing of the information through devices, business cards are most suitable and a handy item that worth a lot for the customers.

This is image title

The impression of the Brand:

The business card is a source that will deliver the first impression of the brand or business towards the potential buyers. It is something handy with the physical touch that develops a direct relationship with the potential market. While going to print business cards that quality, printing style, and overall outlook matters a lot. Because it works as the first impression of the business and its product or services for the potential market. So, the worthy card made with durable material and have an attractive color combination or layout can capture the interest easily.

It contains the company logo, name, design, and color combination that quickly attain the interest of the audience. On other hand, it is an important factor to pay attention to while making the designing and printing decision about the business card.

Direct Marketing Facility:

No doubt there are multiple marketing and promotional tools are available for the product or business promotion. But engraved business cards online is something incredible and handy that provide the physical touch experience. It works as the marketing or promotional element that helps in sharing the details directly to the potential market. With the more physical interaction that the business cards offer to the buyers and business.

The important thing that has to be considered in making the custom business cards, related to the content adjustment, design, and color combination. It helps to capture the buyer’s interest and deliver the right impression towards them.

This is image title

Appreciated in Different Cultures:

The business cards preferably deliver the right knowledge and impression about the product or services. It described the brand position, nature of the products or services, and other relevant skills. In most cultures, it is appreciated to have and share physical business cards as an information-sharing tool. In face-to-face interaction, develops a network and promotes sharing the business information in a circle.

Ease to Provide a Business Reference:

In business cards, online people find multiple opportunities in designing and Printing Services with a significant impression. It helps to make an easy referral related to particular services and a person with a skill set. The business car not only contains the address, contact information, or brand-related knowledge. It provides details about the particular person and reflects the skill set. Multiple factors truly help to describe the right impression of the brand through color, text, and images.

A tool to Develop Trust:

For business growth and development, it is important to gain the trust level of the customers. With the custom business cards, it is easier to attain the trust of the customers. in the competitive business atmosphere for a business survival trust is the only key, that can be over the product or on a company as well. Through the business card, it is easier to exchange and share personal warmth feelings.

With Business Cards Printing, it is easier to show more graphical representation through colors and design. Moreover, with the physical touch, it is easier to give trust feelings or more.

This is image title

Final Consideration!

In the competitive business world, the business card is a source to deliver information and capture the interest of potential buyers. It helps to impress the audience and provide relevant product details and skills that build trust or act as the direct promotional tool.

#business cards printing #visiting card printing online #go print business cards #engraved business cards online #custom business cards #business cards online

Construire une application Web Crud avec Angular | Angulaire 13 CRUD

Angular CRUD désigne une application consistant à créer, lire, mettre à jour et supprimer des fonctionnalités de données. Il s'agit du guide complet sur la création d'applications Web CRUD (créer, lire, mettre à jour, supprimer) à l'aide du nouveau cadre angulaire. L'Angular vient de sortir, et il est livré avec quelques nouvelles fonctionnalités et améliorations.

Tout d'abord, nous installerons Angular en utilisant Angular CLI, puis nous continuerons à développer le frontend et le backend.

1 : Installez Angular et d'autres dépendances.

Si vous avez une ancienne version de @angular/cli, vous pouvez exécuter la commande suivante pour installer les dernières versions.

npm uninstall -g @angular/cli
npm cache verify
npm install -g @angular/cli

Si vous rencontrez des problèmes, veuillez consulter mon How To Update Angular CLI To Version 7Cela vous aidera à mettre à jour votre Angular CLI et vous créerez un tout nouveau projet Angular seven.

Bon, maintenant, si vous tapez la commande suivante, vous pouvez voir que nous avons mis à jour Angular CLI.

Exemple CRUD angulaire 7 |  MEAN Stack Tutoriel

Maintenant, vous allez créer un nouveau projet Angular en utilisant la commande suivante.

ng new angular7crud
cd angular7crud

MEAN Stack CRUD Exemple

Après avoir pénétré dans le dossier du projet, ouvrez le projet dans Visual Studio Code à l'aide de la commande suivante. Si vous ne l'utilisez pas, commencez à l'utiliser. C'est le meilleur éditeur pour le développement Javascript .

code .

Au moment de l'installation, nous avons activé le routage pour notre application. C'est nouveau dans Angular  car il nous invitera lors de l'installation du passe-partout angulaire. Vous pouvez vérifier le fichier appelé fichier app-routing.module.ts  dans le répertoire src >> app .

Ensuite, installez le framework CSS Bootstrap 4 à l'aide de la commande suivante.

npm install bootstrap --save

Maintenant, ajoutez-le dans le  fichier angular.json  .

"styles": [
   "src/styles.css",
   "./node_modules/bootstrap/dist/css/bootstrap.min.css"
 ],

Nous pouvons donc maintenant utiliser les classes Bootstrap 4 dans notre projet. 

Démarrez le serveur de développement angulaire à l'aide de la commande suivante.

ng serve -o

 

Procédure pas à pas angulaire 7

Description du projet

Nous créerons un projet dans lequel les utilisateurs pourront entrer leur nom d'utilisateur  , leur nom commercial  et leur numéro de TPS à partir du formulaire et le soumettre. Si les valeurs sont incorrectes, elles seront validées à l'interface et le formulaire ne sera pas soumis. D'autre part, si toutes les valeurs semblent parfaites, nous enverrons le formulaire à l' API backend , en stockant les valeurs dans la base de données MongoDB .

Alors maintenant, nous allons créer des composants angulaires pour faire le travail.

2 : Générer des composants angulaires

Tapez la commande suivante pour générer des composants angulaires . Nous allons effectuer des opérations de création, de lecture, de mise à jour. Nous allons donc créer trois composants.

ng g c gst-add --spec=false
ng g c gst-get --spec=false
ng g c gst-edit --spec=false

Tutoriel CRUD angulaire

Les trois composants sont automatiquement enregistrés dans un fichier app.module.ts  . Nous devons configurer le routage des composants angulaires dans un fichier app-routing.module.ts  .

// app-routing.module.ts

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { GstAddComponent } from './gst-add/gst-add.component';
import { GstEditComponent } from './gst-edit/gst-edit.component';
import { GstGetComponent } from './gst-get/gst-get.component';

const routes: Routes = [
  {
    path: 'business/create',
    component: GstAddComponent
  },
  {
    path: 'business/edit/:id',
    component: GstEditComponent
  },
  {
    path: 'business',
    component: GstGetComponent
  }
];

@NgModule({
  imports: [RouterModule.forRoot(routes)],
  exports: [RouterModule]
})

export class AppRoutingModule { }

Maintenant, vous pouvez voir à l'intérieur du  fichier app.component.html  que la directive <router-outlet>  est là. Cette directive nous aide à rendre les différents composants en fonction de l'URI de la route.

3 : Créer une navigation angulaire

Écrivez le code suivant dans le  fichier app.component.html  .

<nav class="navbar navbar-expand-sm bg-light">
  <div class="container-fluid">
    <ul class="navbar-nav">
      <li class="nav-item">
        <a routerLink="business/create" class="nav-link" routerLinkActive="active">
          Create Business
        </a>
      </li>
      <li class="nav-item">
        <a routerLink="business" class="nav-link" routerLinkActive="active">
          Business
        </a>
      </li> 
    </ul>
  </div>
</nav>

<div class="container">
  <router-outlet></router-outlet>
</div>

Enregistrez le fichier et accédez au navigateur et cliquez sur deux liens. Vous pouvez voir que nous pouvons voir les différents composants en fonction de la navigation.

4 : Installez l'indicateur de progression du routage angulaire.

Tapez la commande suivante pour installer la  bibliothèque ng2-slim-loading-bar .

npm install ng2-slim-loading-bar --save

Donc, si vous installez des packages tiers en ce moment, il n'est pas compatible avec Angular . Pour combler le fossé entre  les packages angulaires  et tiers, nous devons installer la bibliothèque suivante. C'est ça.

npm install rxjs-compat --save

Maintenant, importez le  SlimLoadingBarModule  dans le  fichier app.module.ts  .

// app.module.ts

import { SlimLoadingBarModule } from 'ng2-slim-loading-bar';

imports: [
    ...
    SlimLoadingBarModule
],

L'étape suivante consiste à inclure le style avec la bibliothèque dans le fichier src >> styles.css  .

@import "../node_modules/ng2-slim-loading-bar/style.css";

5 : Ajout d'événements de routeur.

Angular RouterModule nous donne les modules d'événements suivants.

  1. NavigationDémarrer
  2. NavigationFin
  3. Erreur de navigation
  4. NavigationAnnuler
  5. Routeur
  6. Événement

Maintenant, écrivez le code suivant dans le  fichier app.component.ts  .

// app.component.ts

import { Component } from '@angular/core';
import {SlimLoadingBarService} from 'ng2-slim-loading-bar';
import { NavigationCancel,
        Event,
        NavigationEnd,
        NavigationError,
        NavigationStart,
        Router } from '@angular/router';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  title = 'angular7crud';
  constructor(private _loadingBar: SlimLoadingBarService, private _router: Router) {
    this._router.events.subscribe((event: Event) => {
      this.navigationInterceptor(event);
    });
  }
  private navigationInterceptor(event: Event): void {
    if (event instanceof NavigationStart) {
      this._loadingBar.start();
    }
    if (event instanceof NavigationEnd) {
      this._loadingBar.complete();
    }
    if (event instanceof NavigationCancel) {
      this._loadingBar.stop();
    }
    if (event instanceof NavigationError) {
      this._loadingBar.stop();
    }
  }
}

Il intercepte l'événement de routage et ajoute le composant de barre de chargement à chaque route afin que nous puissions voir l'indication de routage chaque fois que nous modifions les routes.

Le dernier changement pour afficher l'indicateur de routage consiste à ajouter la directive ng2-slim-loading-bar dans le  fichier app.component.html  en haut de la page.

<ng2-slim-loading-bar color="blue"></ng2-slim-loading-bar>

<nav class="navbar navbar-expand-sm bg-light">
  <div class="container-fluid">
    <ul class="navbar-nav">
      <li class="nav-item">
        <a routerLink="business/create" class="nav-link" routerLinkActive="active">
          Create Business
        </a>
      </li>
      <li class="nav-item">
        <a routerLink="business" class="nav-link" routerLinkActive="active">
          Business
        </a>
      </li> 
    </ul>
  </div>
</nav>

<div class="container">
  <router-outlet></router-outlet>
</div>

Enregistrez le fichier et accédez au terminal pour voir s'il y a une erreur et sinon, accédez au navigateur et modifiez les itinéraires, et vous pouvez voir que maintenant nous pouvons voir l'indicateur de routage.

6 : Ajouter un formulaire Bootstrap

Dans le  fichier gst-add.component.html  , ajoutez le  formulaire bootstrap 4 suivant .

<div class="card">
  <div class="card-body">
    <form>
      <div class="form-group">
        <label class="col-md-4">Person Name</label>
        <input type="text" class="form-control" />
      </div>
      <div class="form-group">
        <label class="col-md-4">Business Name </label>
        <input type="text" class="form-control" />
      </div>
      <div class="form-group">
        <label class="col-md-4">Business GST Number </label>
        <input type="text" class="form-control" />
      </div>
      <div class="form-group">
        <button type="submit" class="btn btn-primary">Add Business</button>
      </div>
    </form>
  </div>
</div>

Démo angulaire 7 CRUD

7 : Ajouter une validation de forme angulaire

Nous utiliserons ReactiveFormsModule . Donc, si vous êtes nouveau dans la validation de la forme angulaire , veuillez consulter mon article sur la validation de la forme angulaire  sur ce blog.

Maintenant, importez le  ReactiveFormsModule  dans le  fichier app.module.ts  .

// app.module.ts

import { ReactiveFormsModule } from '@angular/forms';

imports: [
    ...
    ReactiveFormsModule
],

Maintenant, nous devons écrire le code du  fichier app.component.ts  . N'oubliez pas qu'il ne s'agit pas d'un formulaire basé sur un modèle. Nous allons donc modifier le code à l'intérieur du fichier app.component.ts  .

Tout d'abord, nous importons les  modules FormGroup, FormBuilder, Validators  de  @angular/forms .

Créez également un constructeur et instanciez le  FormBuilder .

Écrivez donc le code suivant dans le  fichier gst-add.component.ts  .

// gst-add.component.ts

import { Component, OnInit } from '@angular/core';
import { FormGroup,  FormBuilder,  Validators } from '@angular/forms';

@Component({
  selector: 'app-gst-add',
  templateUrl: './gst-add.component.html',
  styleUrls: ['./gst-add.component.css']
})
export class GstAddComponent implements OnInit {

  angForm: FormGroup;
  constructor(private fb: FormBuilder) {
    this.createForm();
  }

  createForm() {
    this.angForm = this.fb.group({
      person_name: ['', Validators.required ],
      business_name: ['', Validators.required ],
      business_gst_number: ['', Validators.required ]
    });
  }

  ngOnInit() {
  }

}

Nous avons utilisé le générateur de formulaires pour gérer toute la validation. Donc, dans ce constructeur, nous créons un formulaire avec les règles de validation. Dans notre exemple, il y a trois champs. Si le texte d'entrée est vide, cela donnera une erreur et nous devons l'afficher.

Maintenant, écrivez le code suivant dans le  fichier gst-add.component.html  .

<div class="card">
  <div class="card-body">
    <form [formGroup]="angForm" novalidate>
      <div class="form-group">
        <label class="col-md-4">Person Name</label>
        <input type="text" class="form-control" formControlName="person_name" #person_name />
      </div>
      <div *ngIf="angForm.controls['person_name'].invalid && (angForm.controls['person_name'].dirty || angForm.controls['person_name'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['person_name'].errors.required">
          Person Name is required.
        </div>
      </div>
      <div class="form-group">
        <label class="col-md-4">Business Name </label>
        <input type="text" class="form-control" formControlName="business_name" #business_name />
      </div>
      <div *ngIf="angForm.controls['business_name'].invalid && (angForm.controls['business_name'].dirty || angForm.controls['business_name'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['business_name'].errors.required">
          Person Business is required.
        </div>
      </div>
      <div class="form-group">
        <label class="col-md-4">Business GST Number </label>
        <input type="text" class="form-control" formControlName="business_gst_number" #business_gst_number />
      </div>
      <div *ngIf="angForm.controls['business_gst_number'].invalid && (angForm.controls['business_gst_number'].dirty || angForm.controls['business_gst_number'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['business_gst_number'].errors.required">
          Business GST Number is required.
        </div>
      </div>
      <div class="form-group">
        <button type="submit" 
        [disabled]="angForm.pristine || angForm.invalid" 
        class="btn btn-primary">Add Business</button>
      </div>
    </form>
  </div>
</div>

Enregistrez le fichier et accédez au navigateur, et vous pouvez voir si vous ne mettez aucune valeur dans la zone de saisie, vous verrez les erreurs.

Exemple de validation de formulaire angulaire 7

8 : Configurer le HttpClientModule

Importez le  HttpClientModule  dans le  fichier app.module.ts  .

// app.module.ts

import { HttpClientModule } from '@angular/common/http';

imports: [
   ...
    HttpClientModule
 ],

9 : Créer un modèle.

Dans le  dossier src >> app  , créez un fichier appelé  Business.ts  et ajoutez le code suivant.

// Business.ts

export default class Business {
  person_name: String;
  business_name: String;
  business_gst_number: Number;
}

10 : Créez un fichier de service angulaire.

Tapez la commande suivante pour générer le fichier de service.

ng g service business --spec=false

Ainsi, votre fichier principal  business.service.ts  ressemble à ceci.

// business.service.ts

import { Injectable } from '@angular/core';

@Injectable({
  providedIn: 'root'
})
export class BusinessService {

  constructor() { }
}

Maintenant, importez le  fichier business.service.ts  dans le  fichier app.module.ts  .

// app.module.ts

import { BusinessService } from './business.service';

providers: [ BusinessService ],

11 : Soumettre les données au serveur de nœud

Nous devons écrire le code qui enverra la requête HTTP POST avec les données au serveur Node.js et enregistrer les données dans la base de données MongoDB .

Écrivez le code suivant dans le  fichier business.service.ts  .

// business.service.ts

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Injectable({
  providedIn: 'root'
})
export class BusinessService {

  uri = 'http://localhost:4000/business';

  constructor(private http: HttpClient) { }

  addBusiness(person_name, business_name, business_gst_number) {
    const obj = {
      person_name: person_name,
      business_name: business_name,
      business_gst_number: business_gst_number
    };
    console.log(obj);
    this.http.post(`${this.uri}/add`, obj)
        .subscribe(res => console.log('Done'));
  }
}

Nous avons défini l'URL de notre API backend, mais nous n'avons pas encore créé de backend, mais nous le ferons en quelques étapes.

Nous devons ajouter l'événement de clic au bouton Ajouter une entreprise. Ajoutez donc le code suivant dans le fichier gst-add.component.html  .

<div class="form-group">
    <button (click)="addBusiness(person_name.value, business_name.value, business_gst_number.value)"
        [disabled]="angForm.pristine || angForm.invalid" 
        class="btn btn-primary">
        Add Business
     </button>
</div>

Ainsi, lorsqu'il n'y a pas d'erreurs, nous pouvons soumettre le formulaire et il appellera la  fonction addBusiness  du composant . À partir de là, nous appellerons le service angulaire, et le service enverra la requête HTTP Post au serveur Node.js.

Maintenant, ajoutez la  fonction  addBusiness  dans le fichier gst-add.component.ts  . Écrivez donc le code suivant dans  le fichier gst-add.component.ts  .

// gst-add.component.ts

import { Component, OnInit } from '@angular/core';
import { FormGroup,  FormBuilder,  Validators } from '@angular/forms';
import { BusinessService } from '../business.service';

@Component({
  selector: 'app-gst-add',
  templateUrl: './gst-add.component.html',
  styleUrls: ['./gst-add.component.css']
})
export class GstAddComponent implements OnInit {

  angForm: FormGroup;
  constructor(private fb: FormBuilder, private bs: BusinessService) {
    this.createForm();
  }

  createForm() {
    this.angForm = this.fb.group({
      person_name: ['', Validators.required ],
      business_name: ['', Validators.required ],
      business_gst_number: ['', Validators.required ]
    });
  }

  addBusiness(person_name, busines_name, business_gst_number) {
    this.bs.addBusiness(person_name, busines_name, business_gst_number);
  }

  ngOnInit() {
  }

}

Ici, nous avons défini la fonction et également importé le  fichier business.service.ts  . Ensuite, instanciez l'objet dans le constructeur et appelez la fonction du fichier businsess.service.ts .

Nous avons déjà codé la  fonction  addBusiness  dans le fichier business.service.ts  . Maintenant, nous devons configurer l'API backend.

12 : Créer une API back-end Node.js

Dans le dossier racine angulaire, créez un dossier appelé api et accédez à ce dossier. N'oubliez pas qu'il s'agira d'un projet complètement distinct d'Angular. Ainsi, ses node_modules sont différents d'un Angular .

Ouvrez le terminal dans le  dossier api  et tapez la commande suivante.

npm init -y

Installez les modules spécifiques aux nœuds suivants.

npm install --save express body-parser cors mongoose

Je ne redémarre pas le serveur de nœud à chaque fois ; Je change le fichier. J'installe donc le serveur nodemon. Ce qu'il fait, c'est que lorsque je modifie le fichier server.js  , il redémarre  automatiquement le serveur node.js. 

npm install nodemon --save-dev

Maintenant, dans le  dossier api  , créez un fichier appelé  fichier server.js  .

// server.js

const express = require('express'),
    path = require('path'),
    bodyParser = require('body-parser'),
    cors = require('cors'),
    mongoose = require('mongoose');

    const app = express();
    let port = process.env.PORT || 4000;

    const server = app.listen(function(){
        console.log('Listening on port ' + port);
    });

La prochaine chose est de connecter la base de données MongoDB avec notre application node.js.

Si vous n'avez pas installé la base de données MongoDB, installez-la et démarrez le serveur mongodb.

Tapez la commande suivante pour démarrer le   serveur MongoDB .

mongod

Donc, maintenant, je me suis connecté à la base de données.

Créez un fichier appelé  DB.js  dans  le dossier du projet racine api  . Ensuite, écrivez le code suivant dans le fichier DB.js. 

// DB.js

module.exports = {
    DB: 'mongodb://localhost:27017/ng7crud'
 };

Importez ce  fichier DB.js  dans notre  fichier server.js et utilisez la  bibliothèque mongoose  pour configurer la  connexion à la base de données  avec  MongoDB . Nous pouvons également utiliser Mongoose pour enregistrer les données dans la base de données à l'aide de Mongoose ORM.

Écrivez le code suivant dans le fichier server.js  pour connecter notre  application  MongoDB  au serveur Node.js. 

// server.js

const express = require('express'),
    path = require('path'),
    bodyParser = require('body-parser'),
    cors = require('cors'),
    mongoose = require('mongoose'),
    config = require('./DB');

    mongoose.Promise = global.Promise;
    mongoose.connect(config.DB, { useNewUrlParser: true }).then(
      () => {console.log('Database is connected') },
      err => { console.log('Can not connect to the database'+ err)}
    );

    const app = express();
    app.use(bodyParser.json());
    app.use(cors());
    const port = process.env.PORT || 4000;

    const server = app.listen(port, function(){
     console.log('Listening on port ' + port);
    });

Enregistrez le fichier et accédez au terminal et démarrez le serveur de nœud.

nodemon server

Donc, en ce moment, vous avez trois serveurs en cours d'exécution.

  1. Serveur de développement angulaire
  2. Serveur Nodémon
  3. Serveur MongoDB

N'oubliez pas que les trois serveurs fonctionnent correctement sans aucune erreur ; sinon, notre application ne fonctionnera pas.

Étape 13 : Créer un modèle et des itinéraires pour notre application.

Nous devons créer deux dossiers dans le dossier racine de l' api appelés routes et models .

Dans le dossier des modèles  , créez un modèle appelé  Business.js.

// Business.js

const mongoose = require('mongoose');
const Schema = mongoose.Schema;

// Define collection and schema for Business
let Business = new Schema({
  person_name: {
    type: String
  },
  business_name: {
    type: String
  },
  business_gst_number: {
    type: Number
  }
},{
    collection: 'business'
});

module.exports = mongoose.model('Business', Business);

Nous avons donc défini notre schéma pour la collection métier. Nous avons trois champs appelés  person_name, business_name, business_gst_number.

Dans le  dossier routes  , créez un fichier appelé business.route.js.

Écrivez le code CRUD dans le  fichier business.route.js  .

// business.route.js

const express = require('express');
const app = express();
const businessRoutes = express.Router();

// Require Business model in our routes module
let Business = require('../models/Business');

// Defined store route
businessRoutes.route('/add').post(function (req, res) {
  let business = new Business(req.body);
  business.save()
    .then(business => {
      res.status(200).json({'business': 'business in added successfully'});
    })
    .catch(err => {
    res.status(400).send("unable to save to database");
    });
});

// Defined get data(index or listing) route
businessRoutes.route('/').get(function (req, res) {
    Business.find(function (err, businesses){
    if(err){
      console.log(err);
    }
    else {
      res.json(businesses);
    }
  });
});

// Defined edit route
businessRoutes.route('/edit/:id').get(function (req, res) {
  let id = req.params.id;
  Business.findById(id, function (err, business){
      res.json(business);
  });
});

//  Defined update route
businessRoutes.route('/update/:id').post(function (req, res) {
    Business.findById(req.params.id, function(err, next, business) {
    if (!business)
      return next(new Error('Could not load Document'));
    else {
        business.person_name = req.body.person_name;
        business.business_name = req.body.business_name;
        business.business_gst_number = req.body.business_gst_number;

        business.save().then(business => {
          res.json('Update complete');
      })
      .catch(err => {
            res.status(400).send("unable to update the database");
      });
    }
  });
});

// Defined delete | remove | destroy route
businessRoutes.route('/delete/:id').get(function (req, res) {
    Business.findByIdAndRemove({_id: req.params.id}, function(err, business){
        if(err) res.json(err);
        else res.json('Successfully removed');
    });
});

module.exports = businessRoutes;

Nous avons utilisé le modèle mangouste pour enregistrer, mettre à jour et supprimer la base de données. Mongoose est un ORM utilisé dans la base de données MongoDB . Toutes les opérations CRUD sont configurées sur le fichier de route ; nous devons les importer dans le fichier server.js  .

Ainsi, notre  fichier server.js  final ressemble à ceci.

// server.js

const express = require('express'),
    path = require('path'),
    bodyParser = require('body-parser'),
    cors = require('cors'),
    mongoose = require('mongoose'),
    config = require('./DB');

const businessRoute = require('./routes/business.route');
mongoose.Promise = global.Promise;
mongoose.connect(config.DB, { useNewUrlParser: true }).then(
  () => {console.log('Database is connected') },
  err => { console.log('Can not connect to the database'+ err)}
);

const app = express();
app.use(bodyParser.json());
app.use(cors());
app.use('/business', businessRoute);
const port = process.env.PORT || 4000;

const server = app.listen(port, function(){
  console.log('Listening on port ' + port);
});

Étape 14 : Tester la fonctionnalité de données du magasin

Si tous les serveurs sont opérationnels, vous pouvez accéder au navigateur, remplir les données du formulaire et ajouter l'entreprise. Vous pouvez voir quelque chose comme ça sur votre écran si vous réussissez.

Maintenant, nous pouvons vérifier la base de données en utilisant les commandes suivantes.

Tout d'abord, ouvrez le shell mongo sur le 4ème onglet car les trois autres onglets sont occupés pour le moment.

mongo

Ici, nous pouvons voir que les valeurs sont stockées dans la base de données MongoDB. Oui !! Nous avons réussi.

Maintenant, les opérations restantes sont Lire, Mettre à jour et Supprimer.

15 : Afficher les données sur le frontend

Dans le fichier gst-get.component.html  , écrivez le code suivant.

<table class="table table-hover">
  <thead>
  <tr>
      <td>Person Name</td>
      <td>Business Name</td>
      <td>GST Number</td>
      <td colspan="2">Actions</td>
  </tr>
  </thead>

  <tbody>
      <tr *ngFor="let business of businesses">
          <td>{{ business.person_name }}</td>
          <td>{{ business.business_name }}</td>
          <td>{{ business.business_gst_number }}</td>
          <td><a [routerLink]="['/edit', business._id]" class="btn btn-primary">Edit</a></td>
          <td><a [routerLink]="" class="btn btn-danger">Delete</a></td>
      </tr>
  </tbody>
</table>

Maintenant, dans le  fichier business.service.ts  , nous devons écrire la fonction récupérant les données commerciales de la  base de données MongoDB et les affichant dans l' application Angular .

// business.service.ts

getBusinesses() {
    return this
           .http
           .get(`${this.uri}`);
  }

Nous devons inclure ce fichier business.service.ts  et ce fichier Business.ts  dans le fichier  gst-get.component.ts  .

Écrivez le code suivant dans le  fichier gst-get.component.ts  .

// gst-get.component.ts

import { Component, OnInit } from '@angular/core';
import Business from '../Business';
import { BusinessService } from '../business.service';

@Component({
  selector: 'app-gst-get',
  templateUrl: './gst-get.component.html',
  styleUrls: ['./gst-get.component.css']
})
export class GstGetComponent implements OnInit {

  businesses: Business[];

  constructor(private bs: BusinessService) { }

  ngOnInit() {
    this.bs
      .getBusinesses()
      .subscribe((data: Business[]) => {
        this.businesses = data;
    });
  }
}

Enregistrez le fichier, accédez au navigateur et passez à cette URL :  http://localhost:4200/business. Vous pouvez voir la liste des entreprises.

16 : Modifier et mettre à jour les données

D'accord, d'abord, nous devons récupérer les données de la base de données MongoDB en utilisant _id wise et afficher ces données dans le fichier gst-edit.component.html  .

Alors d'abord, écrivez le code suivant dans le  fichier gst-edit.component.ts  .

// gst-edit.component.ts

import { Component, OnInit } from '@angular/core';
import { ActivatedRoute, Router } from '@angular/router';
import { FormGroup,  FormBuilder,  Validators } from '@angular/forms';
import { BusinessService } from '../business.service';

@Component({
  selector: 'app-gst-edit',
  templateUrl: './gst-edit.component.html',
  styleUrls: ['./gst-edit.component.css']
})
export class GstEditComponent implements OnInit {

  business: any = {};
  angForm: FormGroup;

  constructor(private route: ActivatedRoute,
    private router: Router,
    private bs: BusinessService,
    private fb: FormBuilder) {
      this.createForm();
 }

  createForm() {
    this.angForm = this.fb.group({
        person_name: ['', Validators.required ],
        business_name: ['', Validators.required ],
        business_gst_number: ['', Validators.required ]
      });
    }


  ngOnInit() {
    this.route.params.subscribe(params => {
        this.bs.editBusiness(params['id']).subscribe(res => {
          this.business = res;
      });
    });
  }
}

Ici, lorsque le  gst-edit component.ts est  rendu, il appelle la  méthode ngOnInit  et envoie une requête HTTP au serveur de nœud et récupère les données d'un _id à afficher dans le  fichier gst-edit.component.html  .

Maintenant, dans le  fichier business.service.ts  , nous devons coder la  fonction editBusiness  pour envoyer une requête HTTP.

// business.service.ts

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Injectable({
  providedIn: 'root'
})
export class BusinessService {

  uri = 'http://localhost:4000/business';

  constructor(private http: HttpClient) { }

  addBusiness(person_name, business_name, business_gst_number) {
    const obj = {
      person_name: person_name,
      business_name: business_name,
      business_gst_number: business_gst_number
    };
    this.http.post(`${this.uri}/add`, obj)
        .subscribe(res => console.log('Done'));
  }

  getBusinesses() {
    return this
           .http
           .get(`${this.uri}`);
  }

  editBusiness(id) {
    return this
            .http
            .get(`${this.uri}/edit/${id}`);
    }
}

Enfin, nous devons écrire le formulaire dans le fichier gst-edit.component.html  .

<div class="card">
  <div class="card-body">
    <form [formGroup]="angForm" novalidate>
      <div class="form-group">
        <label class="col-md-4">Person Name</label>
        <input type="text" class="form-control" formControlName="person_name" #person_name [(ngModel)] = "business.person_name" />
      </div>
      <div *ngIf="angForm.controls['person_name'].invalid && (angForm.controls['person_name'].dirty || angForm.controls['person_name'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['person_name'].errors.required">
          Person Name is required.
        </div>
      </div>
      <div class="form-group">
        <label class="col-md-4">Business Name </label>
        <input type="text" class="form-control" formControlName="business_name" #business_name [(ngModel)] = "business.business_name" />
      </div>
      <div *ngIf="angForm.controls['business_name'].invalid && (angForm.controls['business_name'].dirty || angForm.controls['business_name'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['business_name'].errors.required">
          Person Business is required.
        </div>
      </div>
      <div class="form-group">
        <label class="col-md-4">Business GST Number </label>
        <input type="text" class="form-control" formControlName="business_gst_number" #business_gst_number [(ngModel)] = "business.business_gst_number" />
      </div>
      <div *ngIf="angForm.controls['business_gst_number'].invalid && (angForm.controls['business_gst_number'].dirty || angForm.controls['business_gst_number'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['business_gst_number'].errors.required">
          Business GST Number is required.
        </div>
      </div>
      <div class="form-group">
        <button (click)="updateBusiness(person_name.value, business_name.value, business_gst_number.value)"
        [disabled]="angForm.invalid" 
        class="btn btn-primary">Update Business</button>
      </div>
    </form>
  </div>
</div>

Enregistrez le fichier, accédez à la page de liste, cliquez sur le bouton Modifier et consultez le formulaire rempli à partir de la base de données.

Vous pouvez également voir l'avertissement comme suit. Ignorez ce tutoriel de démonstration.

forms.js:1193
Il semble que vous utilisiez ngModel sur le même champ de formulaire que formControlName.
La prise en charge de l'utilisation de la propriété d'entrée ngModel et de l'événement ngModelChange avec
des directives de formulaire réactives a été obsolète dans Angular v6 et supprimée
dans Angular v7.

Maintenant, mettez à jour les données. Dans le fichier  business.service.ts  , nous devons écrire la fonction qui met à jour les données.

// business.service.ts

updateBusiness(person_name, business_name, business_gst_number, id) {

    const obj = {
        person_name: person_name,
        business_name: business_name,
        business_gst_number: business_gst_number
      };
    this
      .http
      .post(`${this.uri}/update/${id}`, obj)
      .subscribe(res => console.log('Done'));
  }

Bon, écrivez maintenant la  fonction updateBusiness()  dans le fichier gst-edit.component.ts  .

// gst-edit.component.ts

updateBusiness(person_name, business_name, business_gst_number) {
   this.route.params.subscribe(params => {
      this.bs.updateBusiness(person_name, business_name, business_gst_number, params['id']);
      this.router.navigate(['business']);
});

Enregistrez le fichier et vous pourrez mettre à jour les données.

17 : Supprimer les données.

Ainsi, si vous ne trouvez aucune erreur sur la console, vous pouvez mettre à jour les données avec succès.

J'ai déjà écrit un service d' édition  et  de mise à jour  pour effectuer des appels d'API. Donc jusqu'à présent, Créer, Lire, Mettre à jour  est complet de cet  exemple CRUD angulaire . Maintenant, jetez un œil à  Supprimer .

Nous devons définir l'événement de clic sur le bouton de suppression dans le fichier  gst-get.component.html  .

<tr *ngFor="let business of businesses">
          <td>{{ business.person_name }}</td>
          <td>{{ business.business_name }}</td>
          <td>{{ business.business_gst_number }}</td>
          <td><a [routerLink]="['edit', business._id]" class="btn btn-primary">Edit</a></td>
          <td><a (click) = "deleteBusiness(business._id)" class="btn btn-danger">Delete</a></td>
</tr>

Maintenant, écrivez la  fonction deleteBusiness  dans le  fichier gst-get.component.ts  .

// gst-get.component.ts

deleteBusiness(id) {
    this.bs.deleteBusiness(id).subscribe(res => {
      console.log('Deleted');
    });
  }

Enfin, créez la fonction deleteBusiness()  dans le fichier business.service.ts  .

// business.service.ts

deleteBusiness(id) {
    return this
              .http
              .get(`${this.uri}/delete/${id}`);
  }

Enfin, j'ai terminé la fonctionnalité de suppression.

Ainsi, dans ce didacticiel, nous avons terminé la fonctionnalité CRUD dans Angular.

CODE VN

CODE VN

1646515620

Xây dựng ứng dụng web Crud bằng Angular | Angular 13 CRUD

Angular CRUD có nghĩa là một ứng dụng bao gồm tạo, đọc, cập nhật và xóa các chức năng dữ liệu. Đây là hướng dẫn toàn diện về cách xây dựng các ứng dụng web CRUD (Tạo, Đọc, Cập nhật, Xóa) bằng cách sử dụng Khuôn khổ Angular Mới. Angular vừa được phát hành và nó đi kèm với một số tính năng và cải tiến mới.

Đầu tiên, chúng tôi sẽ cài đặt Angular bằng Angular CLI, sau đó chúng tôi sẽ tiếp tục phát triển frontend và backend.

1: Cài đặt Angular và các phụ thuộc khác.

Nếu bạn có phiên bản @ angle / cli cũ hơn, bạn có thể chạy lệnh sau để cài đặt các phiên bản mới nhất.

npm uninstall -g @angular/cli
npm cache verify
npm install -g @angular/cli

Nếu bạn đang gặp phải bất kỳ sự cố nào, vui lòng xem Cách cập nhật Angular CLI lên phiên bản 7 của tôi . Nó sẽ giúp bạn cập nhật Angular CLI và bạn sẽ tạo một dự án Angular bảy hoàn toàn mới.

Được rồi, bây giờ, nếu bạn gõ lệnh sau, bạn có thể thấy rằng chúng tôi đã cập nhật Angular CLI.

Ví dụ về Angular 7 CRUD |  Hướng dẫn về ngăn xếp MEAN

Bây giờ, bạn sẽ tạo một dự án Angular mới bằng lệnh sau.

ng new angular7crud
cd angular7crud

Ví dụ về MEAN Stack CRUD

Sau khi vào bên trong thư mục dự án, hãy mở dự án trong Visual Studio Code bằng lệnh sau. Nếu bạn không sử dụng nó, sau đó bắt đầu sử dụng nó. Nó là Trình chỉnh sửa tốt nhất để phát triển Javascript .

code .

Tại thời điểm cài đặt, chúng tôi đã bật định tuyến cho ứng dụng của mình. Nó là mới trong Angular  vì nó sẽ nhắc chúng ta trong khi cài đặt boilerplate góc. Bạn có thể kiểm tra tệp có tên tệp app-routing.module.ts  bên trong thư mục src >> app .

Tiếp theo, cài đặt Bootstrap 4 CSS Framework bằng lệnh sau.

npm install bootstrap --save

Bây giờ, thêm nó vào bên trong  tệp angle.json  .

"styles": [
   "src/styles.css",
   "./node_modules/bootstrap/dist/css/bootstrap.min.css"
 ],

Vì vậy, bây giờ chúng ta có thể sử dụng các lớp Bootstrap 4 trong dự án của mình. 

Khởi động máy chủ phát triển Angular bằng lệnh sau.

ng serve -o

 

Hướng dẫn Angular 7

mô tả dự án

Chúng tôi sẽ tạo một dự án trong đó người dùng có thể nhập Tên người dùng  , Tên doanh nghiệp  và Số GST của họ từ biểu mẫu và gửi nó. Nếu các giá trị không chính xác, chúng sẽ xác thực ở giao diện người dùng và biểu mẫu sẽ không được gửi. Mặt khác, nếu tất cả các giá trị có vẻ hoàn hảo, chúng tôi sẽ gửi biểu mẫu đến API phụ trợ , lưu trữ các giá trị bên trong cơ sở dữ liệu MongoDB .

Vì vậy, bây giờ, chúng ta sẽ tạo một số thành phần góc cạnh để thực hiện công việc.

2: Tạo các thành phần Angular

Gõ lệnh sau để tạo các Thành phần Angular . Chúng tôi sẽ thực hiện các thao tác tạo, đọc, cập nhật. Vì vậy, chúng tôi sẽ tạo ra ba thành phần.

ng g c gst-add --spec=false
ng g c gst-get --spec=false
ng g c gst-edit --spec=false

Hướng dẫn sử dụng CRUD góc

Tất cả ba thành phần được đăng ký tự động bên trong tệp app.module.ts  . Chúng ta cần định cấu hình định tuyến của các thành phần góc bên trong tệp app-routing.module.ts  .

// app-routing.module.ts

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { GstAddComponent } from './gst-add/gst-add.component';
import { GstEditComponent } from './gst-edit/gst-edit.component';
import { GstGetComponent } from './gst-get/gst-get.component';

const routes: Routes = [
  {
    path: 'business/create',
    component: GstAddComponent
  },
  {
    path: 'business/edit/:id',
    component: GstEditComponent
  },
  {
    path: 'business',
    component: GstGetComponent
  }
];

@NgModule({
  imports: [RouterModule.forRoot(routes)],
  exports: [RouterModule]
})

export class AppRoutingModule { }

Bây giờ, bạn có thể thấy bên trong  tệp app.component.html  có chỉ thị <router-outlet>  . Chỉ thị này giúp chúng tôi hiển thị các thành phần khác nhau dựa trên URI tuyến.

3: Tạo điều hướng góc

Viết mã sau vào trong  tệp app.component.html  .

<nav class="navbar navbar-expand-sm bg-light">
  <div class="container-fluid">
    <ul class="navbar-nav">
      <li class="nav-item">
        <a routerLink="business/create" class="nav-link" routerLinkActive="active">
          Create Business
        </a>
      </li>
      <li class="nav-item">
        <a routerLink="business" class="nav-link" routerLinkActive="active">
          Business
        </a>
      </li> 
    </ul>
  </div>
</nav>

<div class="container">
  <router-outlet></router-outlet>
</div>

Lưu tệp và truy cập trình duyệt và nhấp vào hai liên kết. Bạn có thể thấy rằng chúng ta có thể thấy các thành phần khác nhau dựa trên điều hướng.

4: Cài đặt Chỉ báo Tiến trình Định tuyến Angular.

Gõ lệnh sau để cài đặt  thư viện ng2-slim-loading-bar .

npm install ng2-slim-loading-bar --save

Vì vậy, nếu bạn cài đặt các gói của bên thứ ba ngay bây giờ, nó sẽ không tương thích với Angular . Để thu hẹp khoảng cách giữa  Angular  và các gói của bên thứ ba, chúng ta cần cài đặt thư viện sau. Đó là nó.

npm install rxjs-compat --save

Bây giờ, nhập  SlimLoadingBarModule  bên trong  tệp app.module.ts  .

// app.module.ts

import { SlimLoadingBarModule } from 'ng2-slim-loading-bar';

imports: [
    ...
    SlimLoadingBarModule
],

Bước tiếp theo là bao gồm tạo kiểu với thư viện bên trong tệp src >> styles.css  .

@import "../node_modules/ng2-slim-loading-bar/style.css";

5: Thêm sự kiện bộ định tuyến.

Angular RouterModule cung cấp cho chúng ta các mô-đun sự kiện sau.

  1. NavigationStart
  2. NavigationEnd
  3. NavigationError
  4. NavigationCancel
  5. Bộ định tuyến
  6. Biến cố

Bây giờ, hãy viết đoạn mã sau bên trong  tệp app.component.ts  .

// app.component.ts

import { Component } from '@angular/core';
import {SlimLoadingBarService} from 'ng2-slim-loading-bar';
import { NavigationCancel,
        Event,
        NavigationEnd,
        NavigationError,
        NavigationStart,
        Router } from '@angular/router';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  title = 'angular7crud';
  constructor(private _loadingBar: SlimLoadingBarService, private _router: Router) {
    this._router.events.subscribe((event: Event) => {
      this.navigationInterceptor(event);
    });
  }
  private navigationInterceptor(event: Event): void {
    if (event instanceof NavigationStart) {
      this._loadingBar.start();
    }
    if (event instanceof NavigationEnd) {
      this._loadingBar.complete();
    }
    if (event instanceof NavigationCancel) {
      this._loadingBar.stop();
    }
    if (event instanceof NavigationError) {
      this._loadingBar.stop();
    }
  }
}

Nó đang làm việc đó là chặn sự kiện định tuyến và thêm thành phần thanh tải vào mọi tuyến đường để chúng tôi có thể thấy chỉ báo định tuyến mỗi khi chúng tôi thay đổi các tuyến đường.

Thay đổi cuối cùng để hiển thị chỉ báo định tuyến là thêm chỉ thị ng2-slim-loading-bar bên trong  tệp app.component.html  ở đầu trang.

<ng2-slim-loading-bar color="blue"></ng2-slim-loading-bar>

<nav class="navbar navbar-expand-sm bg-light">
  <div class="container-fluid">
    <ul class="navbar-nav">
      <li class="nav-item">
        <a routerLink="business/create" class="nav-link" routerLinkActive="active">
          Create Business
        </a>
      </li>
      <li class="nav-item">
        <a routerLink="business" class="nav-link" routerLinkActive="active">
          Business
        </a>
      </li> 
    </ul>
  </div>
</nav>

<div class="container">
  <router-outlet></router-outlet>
</div>

Lưu tệp và đi đến thiết bị đầu cuối để xem có lỗi không và nếu không, hãy vào trình duyệt và thay đổi các tuyến, và bạn có thể thấy rằng bây giờ chúng ta có thể thấy chỉ báo định tuyến.

6: Thêm biểu mẫu Bootstrap

Bên trong  tệp gst-add.component.html  , thêm  biểu mẫu bootstrap 4 sau .

<div class="card">
  <div class="card-body">
    <form>
      <div class="form-group">
        <label class="col-md-4">Person Name</label>
        <input type="text" class="form-control" />
      </div>
      <div class="form-group">
        <label class="col-md-4">Business Name </label>
        <input type="text" class="form-control" />
      </div>
      <div class="form-group">
        <label class="col-md-4">Business GST Number </label>
        <input type="text" class="form-control" />
      </div>
      <div class="form-group">
        <button type="submit" class="btn btn-primary">Add Business</button>
      </div>
    </form>
  </div>
</div>

Angular 7 CRUD Demo

7: Thêm xác thực biểu mẫu góc cạnh

Chúng tôi sẽ sử dụng ReactiveFormsModule . Vì vậy, nếu bạn chưa quen với Angular Form Validation , hãy xem bài viết này của tôi về Angular Form Validation  trên blog này.

Bây giờ, nhập  ReactiveFormsModule  bên trong  tệp app.module.ts  .

// app.module.ts

import { ReactiveFormsModule } from '@angular/forms';

imports: [
    ...
    ReactiveFormsModule
],

Bây giờ, chúng ta cần viết mã cho  tệp app.component.ts  . Hãy nhớ rằng, đây không phải là một biểu mẫu theo hướng mẫu. Vì vậy, chúng tôi sẽ thay đổi mã bên trong tệp app.component.ts  .

Đầu tiên, chúng tôi nhập các  mô-đun FormGroup, FormBuilder, Validators  từ  @ angle / form .

Ngoài ra, hãy tạo một phương thức khởi tạo và khởi tạo  FormBuilder .

Vì vậy, hãy viết đoạn mã sau bên trong  tệp gst-add.component.ts  .

// gst-add.component.ts

import { Component, OnInit } from '@angular/core';
import { FormGroup,  FormBuilder,  Validators } from '@angular/forms';

@Component({
  selector: 'app-gst-add',
  templateUrl: './gst-add.component.html',
  styleUrls: ['./gst-add.component.css']
})
export class GstAddComponent implements OnInit {

  angForm: FormGroup;
  constructor(private fb: FormBuilder) {
    this.createForm();
  }

  createForm() {
    this.angForm = this.fb.group({
      person_name: ['', Validators.required ],
      business_name: ['', Validators.required ],
      business_gst_number: ['', Validators.required ]
    });
  }

  ngOnInit() {
  }

}

Chúng tôi đã sử dụng trình tạo biểu mẫu để xử lý tất cả các xác thực. Vì vậy, trong hàm tạo đó, chúng ta đang tạo một biểu mẫu với các quy tắc xác thực. Trong ví dụ của chúng tôi, có ba trường. Nếu văn bản đầu vào trống, nó sẽ báo lỗi và chúng ta cần hiển thị nó.

Bây giờ, hãy viết đoạn mã sau vào trong  tệp gst-add.component.html  .

<div class="card">
  <div class="card-body">
    <form [formGroup]="angForm" novalidate>
      <div class="form-group">
        <label class="col-md-4">Person Name</label>
        <input type="text" class="form-control" formControlName="person_name" #person_name />
      </div>
      <div *ngIf="angForm.controls['person_name'].invalid && (angForm.controls['person_name'].dirty || angForm.controls['person_name'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['person_name'].errors.required">
          Person Name is required.
        </div>
      </div>
      <div class="form-group">
        <label class="col-md-4">Business Name </label>
        <input type="text" class="form-control" formControlName="business_name" #business_name />
      </div>
      <div *ngIf="angForm.controls['business_name'].invalid && (angForm.controls['business_name'].dirty || angForm.controls['business_name'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['business_name'].errors.required">
          Person Business is required.
        </div>
      </div>
      <div class="form-group">
        <label class="col-md-4">Business GST Number </label>
        <input type="text" class="form-control" formControlName="business_gst_number" #business_gst_number />
      </div>
      <div *ngIf="angForm.controls['business_gst_number'].invalid && (angForm.controls['business_gst_number'].dirty || angForm.controls['business_gst_number'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['business_gst_number'].errors.required">
          Business GST Number is required.
        </div>
      </div>
      <div class="form-group">
        <button type="submit" 
        [disabled]="angForm.pristine || angForm.invalid" 
        class="btn btn-primary">Add Business</button>
      </div>
    </form>
  </div>
</div>

Lưu tệp và vào trình duyệt, và bạn có thể thấy nếu bạn không đặt bất kỳ giá trị nào bên trong hộp nhập liệu, bạn sẽ thấy các lỗi.

Ví dụ về xác thực biểu mẫu Angular 7

8: Định cấu hình HttpClientModule

Nhập  HttpClientModule  bên trong  tệp app.module.ts  .

// app.module.ts

import { HttpClientModule } from '@angular/common/http';

imports: [
   ...
    HttpClientModule
 ],

9: Tạo mô hình.

Bên trong  thư mục ứng dụng src >>  , tạo một tệp có tên  Business.ts  và thêm mã sau.

// Business.ts

export default class Business {
  person_name: String;
  business_name: String;
  business_gst_number: Number;
}

10: Tạo tệp Angular Service.

Nhập lệnh sau để tạo tệp dịch vụ.

ng g service business --spec=false

Vì vậy, tệp business.service.ts  chính của bạn  trông giống như thế này.

// business.service.ts

import { Injectable } from '@angular/core';

@Injectable({
  providedIn: 'root'
})
export class BusinessService {

  constructor() { }
}

Bây giờ, hãy nhập  tệp business.service.ts  vào  tệp app.module.ts  .

// app.module.ts

import { BusinessService } from './business.service';

providers: [ BusinessService ],

11: Gửi dữ liệu đến máy chủ nút

Chúng ta cần viết mã sẽ gửi yêu cầu HTTP POST với dữ liệu đến máy chủ Node.js và lưu dữ liệu vào cơ sở dữ liệu MongoDB .

Viết mã sau vào  tệp business.service.ts  .

// business.service.ts

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Injectable({
  providedIn: 'root'
})
export class BusinessService {

  uri = 'http://localhost:4000/business';

  constructor(private http: HttpClient) { }

  addBusiness(person_name, business_name, business_gst_number) {
    const obj = {
      person_name: person_name,
      business_name: business_name,
      business_gst_number: business_gst_number
    };
    console.log(obj);
    this.http.post(`${this.uri}/add`, obj)
        .subscribe(res => console.log('Done'));
  }
}

Chúng tôi đã xác định URL API phụ trợ của mình, nhưng chúng tôi chưa tạo bất kỳ chương trình phụ trợ nào, nhưng chúng tôi sẽ thực hiện điều đó trong một vài bước.

Chúng ta cần thêm sự kiện nhấp chuột vào Nút Thêm Doanh nghiệp. Vì vậy, hãy thêm mã sau vào trong tệp gst-add.component.html  .

<div class="form-group">
    <button (click)="addBusiness(person_name.value, business_name.value, business_gst_number.value)"
        [disabled]="angForm.pristine || angForm.invalid" 
        class="btn btn-primary">
        Add Business
     </button>
</div>

Vì vậy, khi không có lỗi, chúng tôi có thể gửi biểu mẫu, và nó sẽ gọi  hàm addBusiness  của thành phần . Từ đó, chúng ta sẽ gọi dịch vụ góc và dịch vụ sẽ gửi yêu cầu HTTP Post đến máy chủ Node.js.

Bây giờ, hãy thêm  hàm addBusiness  vào bên trong  tệp gst-add.component.ts  . Vì vậy, hãy viết đoạn mã sau bên trong  tệp gst-add.component.ts  .

// gst-add.component.ts

import { Component, OnInit } from '@angular/core';
import { FormGroup,  FormBuilder,  Validators } from '@angular/forms';
import { BusinessService } from '../business.service';

@Component({
  selector: 'app-gst-add',
  templateUrl: './gst-add.component.html',
  styleUrls: ['./gst-add.component.css']
})
export class GstAddComponent implements OnInit {

  angForm: FormGroup;
  constructor(private fb: FormBuilder, private bs: BusinessService) {
    this.createForm();
  }

  createForm() {
    this.angForm = this.fb.group({
      person_name: ['', Validators.required ],
      business_name: ['', Validators.required ],
      business_gst_number: ['', Validators.required ]
    });
  }

  addBusiness(person_name, busines_name, business_gst_number) {
    this.bs.addBusiness(person_name, busines_name, business_gst_number);
  }

  ngOnInit() {
  }

}

Ở đây, chúng tôi đã xác định hàm và cũng nhập  tệp business.service.ts  . Tiếp theo, khởi tạo đối tượng bên trong hàm tạo và gọi hàm của tệp businsess.service.ts .

Chúng tôi đã mã hóa  hàm addBusiness  bên trong  tệp business.service.ts  . Bây giờ, chúng ta cần định cấu hình API phụ trợ.

12: Tạo một API phụ trợ Node.js

Bên trong thư mục gốc góc, tạo một thư mục có tên api và vào bên trong thư mục đó. Hãy nhớ rằng, nó sẽ là một dự án hoàn toàn riêng biệt với Angular. Vì vậy, node_modules của nó khác với Angular .

Mở thiết bị đầu cuối bên trong  thư mục api  và nhập lệnh sau.

npm init -y

Cài đặt các mô-đun dành riêng cho nút sau.

npm install --save express body-parser cors mongoose

Tôi không khởi động lại máy chủ nút mỗi lần; Tôi thay đổi tệp. Vì vậy, tôi đang cài đặt máy chủ gật đầu. Những gì nó làm là khi tôi sửa đổi tệp server.js  , nó sẽ tự động khởi động lại  máy chủ node.js. 

npm install nodemon --save-dev

Bây giờ, bên trong  thư mục api  , hãy tạo một tệp được gọi là  tệp server.js  .

// server.js

const express = require('express'),
    path = require('path'),
    bodyParser = require('body-parser'),
    cors = require('cors'),
    mongoose = require('mongoose');

    const app = express();
    let port = process.env.PORT || 4000;

    const server = app.listen(function(){
        console.log('Listening on port ' + port);
    });

Điều tiếp theo là kết nối cơ sở dữ liệu MongoDB với ứng dụng node.js của chúng tôi.

Nếu bạn chưa cài đặt cơ sở dữ liệu MongoDB, hãy cài đặt nó và khởi động máy chủ mongodb.

Nhập lệnh sau để khởi động  máy chủ MongoDB  .

mongod

Vì vậy, Bây giờ, tôi đã kết nối với cơ sở dữ liệu.

Tạo một tệp có tên  DB.js  bên trong  thư mục dự án gốc api  . Sau đó, viết đoạn mã sau vào trong tệp DB.js. 

// DB.js

module.exports = {
    DB: 'mongodb://localhost:27017/ng7crud'
 };

Nhập  tệp DB.js này vào bên trong tệp server.js  của chúng tôi  và sử dụng  thư viện mongoose  để thiết lập  kết nối cơ sở dữ liệu  với  MongoDB . Chúng ta cũng có thể sử dụng Mongoose để lưu dữ liệu trong cơ sở dữ liệu bằng Mongoose ORM.

Viết mã sau bên trong tệp  server.js  để kết nối ứng dụng  MongoDB  của chúng tôi với máy chủ Node.js. 

// server.js

const express = require('express'),
    path = require('path'),
    bodyParser = require('body-parser'),
    cors = require('cors'),
    mongoose = require('mongoose'),
    config = require('./DB');

    mongoose.Promise = global.Promise;
    mongoose.connect(config.DB, { useNewUrlParser: true }).then(
      () => {console.log('Database is connected') },
      err => { console.log('Can not connect to the database'+ err)}
    );

    const app = express();
    app.use(bodyParser.json());
    app.use(cors());
    const port = process.env.PORT || 4000;

    const server = app.listen(port, function(){
     console.log('Listening on port ' + port);
    });

Lưu tệp và đi đến thiết bị đầu cuối và khởi động máy chủ nút.

nodemon server

Vì vậy, ngay bây giờ, bạn có ba máy chủ đang chạy.

  1. Máy chủ phát triển góc
  2. Máy chủ Nodemon
  3. Máy chủ MongoDB

Hãy nhớ rằng, cả ba máy chủ đều chạy tốt mà không có bất kỳ lỗi nào; nếu không, ứng dụng của chúng tôi sẽ không hoạt động.

Bước 13: Tạo mô hình và các tuyến đường cho ứng dụng của chúng tôi.

Chúng ta cần tạo hai thư mục bên trong thư mục gốc api được gọi là các tuyếnmô hình .

Trong thư mục mô hình  , hãy tạo một mô hình có tên là  Business.js.

// Business.js

const mongoose = require('mongoose');
const Schema = mongoose.Schema;

// Define collection and schema for Business
let Business = new Schema({
  person_name: {
    type: String
  },
  business_name: {
    type: String
  },
  business_gst_number: {
    type: Number
  }
},{
    collection: 'business'
});

module.exports = mongoose.model('Business', Business);

Vì vậy, chúng tôi đã xác định lược đồ của mình cho bộ sưu tập doanh nghiệp. Chúng tôi có ba trường được gọi là  person_name, business_name, business_gst_number.

Trong  thư mục định tuyến  , hãy tạo một tệp có tên business.route.js.

Viết mã CRUD bên trong  tệp business.route.js  .

// business.route.js

const express = require('express');
const app = express();
const businessRoutes = express.Router();

// Require Business model in our routes module
let Business = require('../models/Business');

// Defined store route
businessRoutes.route('/add').post(function (req, res) {
  let business = new Business(req.body);
  business.save()
    .then(business => {
      res.status(200).json({'business': 'business in added successfully'});
    })
    .catch(err => {
    res.status(400).send("unable to save to database");
    });
});

// Defined get data(index or listing) route
businessRoutes.route('/').get(function (req, res) {
    Business.find(function (err, businesses){
    if(err){
      console.log(err);
    }
    else {
      res.json(businesses);
    }
  });
});

// Defined edit route
businessRoutes.route('/edit/:id').get(function (req, res) {
  let id = req.params.id;
  Business.findById(id, function (err, business){
      res.json(business);
  });
});

//  Defined update route
businessRoutes.route('/update/:id').post(function (req, res) {
    Business.findById(req.params.id, function(err, next, business) {
    if (!business)
      return next(new Error('Could not load Document'));
    else {
        business.person_name = req.body.person_name;
        business.business_name = req.body.business_name;
        business.business_gst_number = req.body.business_gst_number;

        business.save().then(business => {
          res.json('Update complete');
      })
      .catch(err => {
            res.status(400).send("unable to update the database");
      });
    }
  });
});

// Defined delete | remove | destroy route
businessRoutes.route('/delete/:id').get(function (req, res) {
    Business.findByIdAndRemove({_id: req.params.id}, function(err, business){
        if(err) res.json(err);
        else res.json('Successfully removed');
    });
});

module.exports = businessRoutes;

Chúng tôi đã sử dụng mô hình mongoose để lưu, cập nhật và xóa cơ sở dữ liệu. Mongoose là một ORM được sử dụng trong cơ sở dữ liệu MongoDB . Chúng tôi có tất cả các hoạt động CRUD được thiết lập trên tệp tuyến đường; chúng ta cần nhập chúng vào bên trong tệp server.js  .

Vì vậy, tệp server.js  cuối cùng của chúng tôi  trông như thế này.

// server.js

const express = require('express'),
    path = require('path'),
    bodyParser = require('body-parser'),
    cors = require('cors'),
    mongoose = require('mongoose'),
    config = require('./DB');

const businessRoute = require('./routes/business.route');
mongoose.Promise = global.Promise;
mongoose.connect(config.DB, { useNewUrlParser: true }).then(
  () => {console.log('Database is connected') },
  err => { console.log('Can not connect to the database'+ err)}
);

const app = express();
app.use(bodyParser.json());
app.use(cors());
app.use('/business', businessRoute);
const port = process.env.PORT || 4000;

const server = app.listen(port, function(){
  console.log('Listening on port ' + port);
});

Bước 14: Kiểm tra chức năng dữ liệu lưu trữ

Nếu tất cả các máy chủ đang hoạt động, bạn có thể truy cập trình duyệt, điền vào dữ liệu biểu mẫu và thêm doanh nghiệp. Bạn có thể thấy một cái gì đó như thế này trên màn hình của bạn nếu bạn thành công.

Bây giờ, chúng ta có thể kiểm tra cơ sở dữ liệu bằng các lệnh sau.

Đầu tiên, hãy mở trình bao mongo trên tab thứ 4 vì tất cả ba tab còn lại đều bị chiếm dụng tại thời điểm này.

mongo

Ở đây, chúng ta có thể thấy rằng các giá trị được lưu trữ trong cơ sở dữ liệu MongoDB. Vâng!! Chúng tôi đã thành công.

Bây giờ, các thao tác còn lại là Đọc, Cập nhật và Xóa.

15: Hiển thị dữ liệu trên giao diện người dùng

Trong tệp gst-get.component.html  , hãy viết mã sau.

<table class="table table-hover">
  <thead>
  <tr>
      <td>Person Name</td>
      <td>Business Name</td>
      <td>GST Number</td>
      <td colspan="2">Actions</td>
  </tr>
  </thead>

  <tbody>
      <tr *ngFor="let business of businesses">
          <td>{{ business.person_name }}</td>
          <td>{{ business.business_name }}</td>
          <td>{{ business.business_gst_number }}</td>
          <td><a [routerLink]="['/edit', business._id]" class="btn btn-primary">Edit</a></td>
          <td><a [routerLink]="" class="btn btn-danger">Delete</a></td>
      </tr>
  </tbody>
</table>

Bây giờ, bên trong  tệp business.service.ts  , chúng ta cần viết hàm tìm nạp dữ liệu nghiệp vụ từ  cơ sở dữ liệu MongoDB và hiển thị nó tại ứng dụng Angular .

// business.service.ts

getBusinesses() {
    return this
           .http
           .get(`${this.uri}`);
  }

Chúng tôi cần bao gồm tệp business.service.ts  này và tệp Business.ts  bên trong tệp  gst-get.component.ts  .

Viết đoạn mã sau vào trong  tệp gst-get.component.ts  .

// gst-get.component.ts

import { Component, OnInit } from '@angular/core';
import Business from '../Business';
import { BusinessService } from '../business.service';

@Component({
  selector: 'app-gst-get',
  templateUrl: './gst-get.component.html',
  styleUrls: ['./gst-get.component.css']
})
export class GstGetComponent implements OnInit {

  businesses: Business[];

  constructor(private bs: BusinessService) { }

  ngOnInit() {
    this.bs
      .getBusinesses()
      .subscribe((data: Business[]) => {
        this.businesses = data;
    });
  }
}

Lưu tệp, truy cập trình duyệt và chuyển sang URL này:  http: // localhost: 4200 / business. Bạn có thể xem danh sách của các doanh nghiệp.

16: Chỉnh sửa và cập nhật dữ liệu

Được rồi, trước tiên, chúng ta cần tìm nạp dữ liệu từ cơ sở dữ liệu MongoDB bằng _id khôn ngoan và hiển thị dữ liệu đó trong tệp gst-edit.component.html  .

Vì vậy, trước tiên, hãy viết đoạn mã sau bên trong  tệp gst-edit.component.ts  .

// gst-edit.component.ts

import { Component, OnInit } from '@angular/core';
import { ActivatedRoute, Router } from '@angular/router';
import { FormGroup,  FormBuilder,  Validators } from '@angular/forms';
import { BusinessService } from '../business.service';

@Component({
  selector: 'app-gst-edit',
  templateUrl: './gst-edit.component.html',
  styleUrls: ['./gst-edit.component.css']
})
export class GstEditComponent implements OnInit {

  business: any = {};
  angForm: FormGroup;

  constructor(private route: ActivatedRoute,
    private router: Router,
    private bs: BusinessService,
    private fb: FormBuilder) {
      this.createForm();
 }

  createForm() {
    this.angForm = this.fb.group({
        person_name: ['', Validators.required ],
        business_name: ['', Validators.required ],
        business_gst_number: ['', Validators.required ]
      });
    }


  ngOnInit() {
    this.route.params.subscribe(params => {
        this.bs.editBusiness(params['id']).subscribe(res => {
          this.business = res;
      });
    });
  }
}

Tại đây, khi  gst-edit component.ts  kết xuất, nó sẽ gọi  phương thức ngOnInit  và gửi một yêu cầu HTTP đến máy chủ nút và tìm nạp dữ liệu từ một _id để hiển thị bên trong  tệp gst-edit.component.html  .

Bây giờ, bên trong  tệp business.service.ts  , chúng ta cần mã  hóa hàm editBusiness  để gửi một yêu cầu HTTP.

// business.service.ts

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Injectable({
  providedIn: 'root'
})
export class BusinessService {

  uri = 'http://localhost:4000/business';

  constructor(private http: HttpClient) { }

  addBusiness(person_name, business_name, business_gst_number) {
    const obj = {
      person_name: person_name,
      business_name: business_name,
      business_gst_number: business_gst_number
    };
    this.http.post(`${this.uri}/add`, obj)
        .subscribe(res => console.log('Done'));
  }

  getBusinesses() {
    return this
           .http
           .get(`${this.uri}`);
  }

  editBusiness(id) {
    return this
            .http
            .get(`${this.uri}/edit/${id}`);
    }
}

Cuối cùng, chúng ta cần viết biểu mẫu bên trong tệp gst-edit.component.html  .

<div class="card">
  <div class="card-body">
    <form [formGroup]="angForm" novalidate>
      <div class="form-group">
        <label class="col-md-4">Person Name</label>
        <input type="text" class="form-control" formControlName="person_name" #person_name [(ngModel)] = "business.person_name" />
      </div>
      <div *ngIf="angForm.controls['person_name'].invalid && (angForm.controls['person_name'].dirty || angForm.controls['person_name'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['person_name'].errors.required">
          Person Name is required.
        </div>
      </div>
      <div class="form-group">
        <label class="col-md-4">Business Name </label>
        <input type="text" class="form-control" formControlName="business_name" #business_name [(ngModel)] = "business.business_name" />
      </div>
      <div *ngIf="angForm.controls['business_name'].invalid && (angForm.controls['business_name'].dirty || angForm.controls['business_name'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['business_name'].errors.required">
          Person Business is required.
        </div>
      </div>
      <div class="form-group">
        <label class="col-md-4">Business GST Number </label>
        <input type="text" class="form-control" formControlName="business_gst_number" #business_gst_number [(ngModel)] = "business.business_gst_number" />
      </div>
      <div *ngIf="angForm.controls['business_gst_number'].invalid && (angForm.controls['business_gst_number'].dirty || angForm.controls['business_gst_number'].touched)" class="alert alert-danger">
        <div *ngIf="angForm.controls['business_gst_number'].errors.required">
          Business GST Number is required.
        </div>
      </div>
      <div class="form-group">
        <button (click)="updateBusiness(person_name.value, business_name.value, business_gst_number.value)"
        [disabled]="angForm.invalid" 
        class="btn btn-primary">Update Business</button>
      </div>
    </form>
  </div>
</div>

Lưu tệp, đi đến trang danh sách, nhấp vào nút chỉnh sửa và xem biểu mẫu được điền từ cơ sở dữ liệu.

Bạn cũng có thể thấy cảnh báo như sau. Bỏ qua hướng dẫn demo này.

form.js: 1193
Có vẻ như bạn đang sử dụng ngModel trên cùng một trường biểu mẫu với formControlName.
Hỗ trợ sử dụng thuộc tính đầu vào ngModel và sự kiện ngModelChange với các
chỉ thị biểu mẫu phản ứng đã không được chấp nhận trong Angular v6 và bị loại bỏ
trong Angular v7.

Bây giờ, hãy cập nhật dữ liệu. Bên trong tệp  business.service.ts  , chúng ta cần viết hàm cập nhật dữ liệu.

// business.service.ts

updateBusiness(person_name, business_name, business_gst_number, id) {

    const obj = {
        person_name: person_name,
        business_name: business_name,
        business_gst_number: business_gst_number
      };
    this
      .http
      .post(`${this.uri}/update/${id}`, obj)
      .subscribe(res => console.log('Done'));
  }

Được rồi, bây giờ hãy viết hàm  updateBusiness ()  bên trong tệp gst-edit.component.ts  .

// gst-edit.component.ts

updateBusiness(person_name, business_name, business_gst_number) {
   this.route.params.subscribe(params => {
      this.bs.updateBusiness(person_name, business_name, business_gst_number, params['id']);
      this.router.navigate(['business']);
});

Lưu tệp và bạn sẽ có thể cập nhật dữ liệu.

17: Xóa dữ liệu.

Vì vậy, nếu bạn không tìm thấy lỗi nào trên bảng điều khiển, bạn có thể cập nhật dữ liệu thành công.

Tôi đã viết một dịch vụ chỉnh sửa  và  cập nhật  để thực hiện các lệnh gọi API. Vì vậy, cho đến nay, Tạo, Đọc, Cập nhật  đã hoàn tất cho  Ví dụ Angular CRUD này . Bây giờ, hãy xem  Xóa .

Chúng ta cần xác định sự kiện nhấp chuột vào nút xóa bên trong tệp  gst-get.component.html  .

<tr *ngFor="let business of businesses">
          <td>{{ business.person_name }}</td>
          <td>{{ business.business_name }}</td>
          <td>{{ business.business_gst_number }}</td>
          <td><a [routerLink]="['edit', business._id]" class="btn btn-primary">Edit</a></td>
          <td><a (click) = "deleteBusiness(business._id)" class="btn btn-danger">Delete</a></td>
</tr>

Bây giờ, hãy viết  hàm deleteBusiness  bên trong  tệp gst-get.component.ts  .

// gst-get.component.ts

deleteBusiness(id) {
    this.bs.deleteBusiness(id).subscribe(res => {
      console.log('Deleted');
    });
  }

Cuối cùng, tạo hàm deleteBusiness ()  bên trong tệp business.service.ts  .

// business.service.ts

deleteBusiness(id) {
    return this
              .http
              .get(`${this.uri}/delete/${id}`);
  }

Cuối cùng, tôi đã hoàn thành chức năng xóa.

Như vậy, trong hướng dẫn này, chúng ta đã hoàn thành Chức năng CRUD trong Angular.