Karim Aya

Karim Aya

1568858965

Building reactive forms in Angular 8

Forms controls and form groups in Angular

Form controls are basically classes that can hold both the data values and the validation information of any form element, which means to say every form input you have in a reactive form should be bound by a form control. They are the basic units that make up reactive forms.

Form groups are constructs that basically wrap a collection of form controls. Just as the control gives you access to the state of an element, the group gives the same access, but to the state of the wrapped controls. Every single form control in the form group is identified by name when initializing.

Generating form controls

Setting up form controls, especially for very long forms, can quickly become both monotonous and stressful. Angular provides a helper service to solve this problem so that you can always obey the DRY concept of avoiding repetition. This service is called the form builder service.

Before we start…

To be able to follow through this article’s demonstration, you should have:

  • Node version 11.0 installed on your machine
  • Node Package Manager version 6.7 (usually ships with the Node installation)
  • Angular CLI version 8.0
  • The latest version of Angular (version 8)
// run the command in a terminal
ng version
  • Confirm that you are using version 8, and update to 8 if you are not.
  • Download this tutorial’s starter project here to follow through the demonstrations.
  • Unzip the project and initialize the Node modules in your terminal with this command:
npm install

Other things that would be nice to have are:

  • A working knowledge of the Angular framework at a beginner level
  • Familiarity with form controls in Angular will be a plus but not a requirement

_________________________________________________________________________________

You may also like: Angular Architecture Patterns and Best Practices

________________________________________________________________________________

Demo

In this tutorial, you will be taken through a code-along journey building a reactive form with the form builder. If you have followed this post from the start, you will have downloaded and opened the starter project in VS Code. If you open the employee.component.ts, file it should look like this:

import { Component, OnInit } from '@angular/core';
import { FormControl, FormGroup } from '@angular/forms'
@Component({
  selector: 'app-employee',
  templateUrl: './employee.component.html',
  styleUrls: ['./employee.component.css']
})
export class EmployeeComponent implements OnInit {
  bioSection = new FormGroup({
    firstName: new FormControl(''),
    lastName: new FormControl(''),
    age: new FormControl(''),
    stackDetails: new FormGroup({
      stack: new FormControl(''),
      experience: new FormControl('')
    }),
    address: new FormGroup({
        country: new FormControl(''),
        city: new FormControl('')
    })
  });
constructor() { }
ngOnInit() {
  }
  callingFunction() {
    console.log(this.bioSection.value);
   }
}

You can see that every single form control — and even the form group that partitions it — is spelled out, so over time, you as the developer keep repeating yourself. The form builder helps to solve this efficiency problem. To use the form builder, you must first register it.

Registering the form builder

To register the form builder in a component, the first thing to do is import it from Angular forms:

import { FormBuilder } from ‘@angular/forms’;

The next step is to inject the form builder service, which is an injectable provider that comes with the reactive forms module. You can then use the form builder after injecting it. Navigate to the employee.component.ts file and copy in the code block below:

import { Component, OnInit } from '@angular/core';
import { FormBuilder } from '@angular/forms'
@Component({
  selector: 'app-employee',
  templateUrl: './employee.component.html',
  styleUrls: ['./employee.component.css']
})
export class EmployeeComponent implements OnInit {
  bioSection = this.fb.group({
    firstName: [''],
    lastName: [''],
    age: [''],
    stackDetails: this.fb.group({
      stack: [''],
      experience: ['']
    }),
    address: this.fb.group({
        country: [''],
        city: ['']
    })
  });
constructor(private fb: FormBuilder) { }
ngOnInit() {
  }
  callingFunction() {
    console.log(this.bioSection.value);
   }
}

This does exactly the same thing as the previous code block you saw at the start, but you can see there is a lot less code and more structure — and, thus, optimal usage of resources. Form builders not only help to make your reactive forms’ code efficient, but they are also important for form validation.

Form validation

Using reactive forms in Angular, you can validate your forms inside the form builders. Run your application in development with the command:

ng serve

You will discover that the form submits even when you do not input values into the text boxes. This can easily be checked with form validators in reactive forms. The first thing to do, as with all elements of reactive forms, is to import it from Angular forms.

<button type=”submit” [disabled]=”!bioSection.valid”>Submit Application</button>

If you run your application now, you will see that if you do not set an input for first name, you cannot submit the form — isn’t that cool? There are many more cool form validation tips you can get from the official guide here.

Displaying input values and status

The last thing you should know is how to use the value and status properties to display, in real time, the input values of your reactive form and whether it can be submitted or not.

The reactive forms API lets you use the value and status properties on your form group or form controls in the template section. Open your employee.component.html file and copy in the code block below:

<form [formGroup]="bioSection" (ngSubmit)="callingFunction()">
    <h3>Bio Details
</h3>

<label>
First Name:
<input type=“text” formControlName=“firstName”>
</label> <br>
<label>
Last Name:
<input type=“text” formControlName=“lastName”>
</label> <br>
<label>
Age:
<input type=“text” formControlName=“age”>
</label>
<div formGroupName=“stackDetails”>
<h3>Stack Details</h3>

&lt;label&gt;
  Stack:
  &lt;input type="text" formControlName="stack"&gt;
&lt;/label&gt; &lt;br&gt;

&lt;label&gt;
  Experience:
  &lt;input type="text" formControlName="experience"&gt;
&lt;/label&gt;

</div>
<div formGroupName=“address”>
<h3>Address</h3>

&lt;label&gt;
  Country:
  &lt;input type="text" formControlName="country"&gt;
&lt;/label&gt; &lt;br&gt;

&lt;label&gt;
  City:
  &lt;input type="text" formControlName="city"&gt;
&lt;/label&gt;

</div>
<button type=“submit” [disabled]=“!bioSection.valid”>Submit Application</button>
<p>
Real-time data: {{ bioSection.value | json }}
</p>
<p>
Your form status is : {{ bioSection.status }}
</p>
</form>

This displays both the value and the status for submission for you in the interface as you use the form. The complete code to this tutorial can be found here on GitHub.

Conclusion

This article gives an overview of the form builder and how it is a great efficiency enabler for form controls and form groups. It also shows how important it can be for handling form validation easily with reactive forms. Happy hacking!


import { Validators } from ‘@angular/forms’;

You can now play around with the validators by specifying the form controls that must be filled in order for the submit button to be active. Copy the code block below into the employee.component.ts file:

The last thing to do is to make sure the submit button’s active settings are set accordingly. Navigate to the employee.component.html file and make sure the submit statement looks like this:

Further Reading

Angular 8 Pagination Example and Tutorial

Angular 8 Material Design Tutorial & Example

Build a web app using Nestjs, Fastify, MongoDB and Angular 8

Originally published by Nwose Lotanna  at blog.logrocket.com

===================================================================

Thanks for reading :heart: If you liked this post, share it with all of your programming buddies! Follow me on Facebook | Twitter



#angular #web-development

What is GEEK

Buddha Community

Building reactive forms in Angular 8

Yogi Gurjar

1600308055

Laravel 8 Form Validation Tutorial

Laravel 8 form validation example. In this tutorial, i will show you how to submit form with validation in laravel 8.

And you will learn how to store form data in laravel 8. Also validate form data before store to db.

How to Validate Form Data in Laravel 8

  1. Step 1 – Install Laravel 8 Application
  2. Step 2 – Configuring Database using Env File
  3. Step 3 – Create Model & Migration File For Form
  4. Step 4 – Create Routes
  5. Step 5 – Creating Controller
  6. Step 6 – Create Blade File For Form
  7. Step 7 – Start Development Server
  8. Step 8 – Run Laravel 8 Form Validation App On Browser

https://laratutorials.com/laravel-8-form-validation-example-tutorial/

#laravel 8 form validation #laravel 8 form validation tutorial #laravel 8 form validation - google search #how to validate form data in laravel 8 #form validation in laravel 8

Clara  Gutmann

Clara Gutmann

1598705160

Angular 8 Forms | Angular Reactive and Template Forms

Angular Forms are used to handle the user’s input. We can use Angular form in our application to enable users to log in, update profiles, enter information, and to perform many other data-entry tasks.

If you are new to Angular, then check out myAngular Tutorial. If you do not know how to upgrade to Angular 8 via Angular CLI, then check out my Angular Upgrade tutorial. Managing user input with forms is the cornerstone of many web applications.

The web app uses forms to enable the users to log in, to update a profile, to enter sensitive information, and to perform many data-entry tasks.

#angular #angular 8 #angular reactive

I am Developer

1608866530

Angular 11 Reactive Forms Validation Tutorial

Reactive form validation in Angular 11 app. In this tutorial, i will show you how to use reactive form validation in angular 11 app.

As well as, and you will learn how use reactive form validation in angular 11. And also use reactive form with formGroup for validation in angular 11 app.

Reactive Form Validation In Angular 11
Step 1 – Create New Angular App
Step 2 – Import Form Module
Step 3 – Add Code on View File
Step 4 – Use Component ts File
Step 5 – Start Angular App

https://www.tutsmake.com/angular-11-reactive-forms-validation-tutorial-example/

#reactive form validation in angular 11 #angular 11/10/9/8/7 reactive forms validation example #angular 11 form validation example

Yogi Gurjar

1600307723

Laravel 8 Form Example Tutorial - Complete Guide

Laravel 8 form example. In this tutorial, i would love to show you how to create form in laravel. And how to insert data into database using form in laravel 8.

How to Submit Form Data into Database in Laravel 8

  1. Step 1 – Install Laravel 8 Application
  2. Step 2 – Configuring Database using Env File
  3. Step 3 – Create Model & Migration File For Add Blog Post Form
  4. Step 4 – Create Routes
  5. Step 5 – Creating Controller
  6. Step 6 – Create Blade File For Add Blog Post Form
  7. Step 7 – Start Development Server
  8. Step 8 – Run Laravel 8 Form App On Browser

https://laratutorials.com/laravel-8-form-example-tutorial/

#insert form data into database using laravel #laravel bootstrap form #laravel post forms #laravel 8 form tutorial #laravel 8 form example #laravel 8 form submit tutorial

Christa  Stehr

Christa Stehr

1598940617

Install Angular - Angular Environment Setup Process

Angular is a TypeScript based framework that works in synchronization with HTML, CSS, and JavaScript. To work with angular, domain knowledge of these 3 is required.

  1. Installing Node.js and npm
  2. Installing Angular CLI
  3. Creating workspace
  4. Deploying your First App

In this article, you will get to know about the Angular Environment setup process. After reading this article, you will be able to install, setup, create, and launch your own application in Angular. So let’s start!!!

Angular environment setup

Install Angular in Easy Steps

For Installing Angular on your Machine, there are 2 prerequisites:

  • Node.js
  • npm Package Manager
Node.js

First you need to have Node.js installed as Angular require current, active LTS or maintenance LTS version of Node.js

Download and Install Node.js version suitable for your machine’s operating system.

Npm Package Manager

Angular, Angular CLI and Angular applications are dependent on npm packages. By installing Node.js, you have automatically installed the npm Package manager which will be the base for installing angular in your system. To check the presence of npm client and Angular version check of npm client, run this command:

  1. npm -v

Installing Angular CLI

  • Open Terminal/Command Prompt
  • To install Angular CLI, run the below command:
  1. npm install -g @angular/cli

installing angular CLI

· After executing the command, Angular CLI will get installed within some time. You can check it using the following command

  1. ng --version

Workspace Creation

Now as your Angular CLI is installed, you need to create a workspace to work upon your application. Methods for it are:

  • Using CLI
  • Using Visual Studio Code
1. Using CLI

To create a workspace:

  • Navigate to the desired directory where you want to create your workspace using cd command in the Terminal/Command prompt
  • Then in the directory write this command on your terminal and provide the name of the app which you want to create. In my case I have mentioned DataFlair:
  1. Ng new YourAppName

create angular workspace

  • After running this command, it will prompt you to select from various options about the CSS and other functionalities.

angular CSS options

  • To leave everything to default, simply press the Enter or the Return key.

angular setup

#angular tutorials #angular cli install #angular environment setup #angular version check #download angular #install angular #install angular cli