Dylan North

Dylan North

1565343454

Angular NgFor Tutorial With Example | NgForOf Directive

Originally published by Krunal at appdividend.com

The ngForOf is generally used in the shorthand form *ngFor. The core directive ngFor allows us to build data presentation lists and tables in our HTML templates. When we need to display data in Angular, we use the ngFor directive.

Content Overview 

  • 1 Angular NgFor Tutorial With Example
  • 2 Step 1: Install Angular
  • 3 Step 2: Create a Model file.
  • 4 Step 3: Use a ngFor directive to render HTML table
  • 5 Step 4: How to stripe a table using even and odd
  • 6 Step 5: Identifying the first and the last row of a table

Angular NgFor Tutorial With Example

Let’s see the Syntax of the NgFor directive.

<ng-template *ngFor="let item of items; index as i; trackBy: trackByFn">...</ng-template>

Let’s take an example of the ngFor directive in Angular.

Step 1: Install Angular

If you do not have the latest Angular CLI, then you need to update your CLI. For more guidance, see this tutorial. Now, create a new project using the following command.

ng new angfor

 

Now, go inside the folder and open the folder in Visual Studio Code.

Next, install the Bootstrap 4 CSS Framework using the following command.

npm install bootstrap --save

Now, add the bootstrap css file inside the angular.json file.

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

Step 2: Create a Model file.

Inside the src >> app folder, create one file called Character.ts file and add the following code inside it.

// Character.ts

export default class Character {
actor_name: String;
character_name: String;
gender: String;
status: String;
}

We will display the Game of Thrones characters and their properties like actor_name,character_namegenderstatus, etc.

Now, create an array of data inside the app.component.ts file.

// app.component.ts

import { Component } from ‘@angular/core’;
import Character from ‘./Character’;
@Component({
selector: ‘app-root’,
templateUrl: ‘./app.component.html’,
styleUrls: [‘./app.component.css’]
})
export class AppComponent {
characters: Character[] = [
{
actor_name: ‘Peter Dinklage’,
character_name: ‘Tyrion Lannister’,
gender: ‘Male’,
status: ‘Alive’
},
{
actor_name: ‘Sean Bean’,
character_name: ‘Ned Stark’,
gender: ‘Male’,
status: ‘Dead’
},
{
actor_name: ‘Emilia Clark’,
character_name: ‘Khaleesi’,
gender: ‘Female’,
status: ‘Alive’
},
{
actor_name: ‘Catelyn Stark’,
character_name: ‘Michelle Fairley’,
gender: ‘Female’,
status: ‘Dead’
}
];
}

So, now we have data that can be rendered inside an HTML view using the ngFor directive.

Step 3: Use a ngFor directive to render HTML table

Let’s create the component so that we can have a working HTML. Write the following code inside an app.component.html file.

<!-- app.component.html -->

<div class=“container”>
<table class=“table table-striped”>
<thead>
<tr>
<th>Actor Name</th>
<th>Character Name</th>
<th>Gender</th>
<th>Status</th>
</tr>
</thead>
<tbody>
<tr *ngFor=“let character of characters”>
<td>{{ character.actor_name }}</td>
<td>{{ character.character_name }}</td>
<td>{{ character.gender }}</td>
<td>{{ character.status }}</td>
</tr>
</tbody>
</table>
</div>

Save the file and go to the terminal and start the angular dev server.

ng serve --open

See the output in the browser.

 

So, the ngFor directive has generated the HTML rows.

This template will generate the HTML table that we showed just above. We can see in this example the (most common) syntax for using ngFor is following.

  • We are passing to ngFor an iteration expression
  • The loop variable named character is defined using the keyword let, which is consistent with Javascript syntax.

Let’s add an index in the table. Write the following code inside an app.component.html file.

<!-- app.component.html -->

<div class=“container”>
<table class=“table table-striped”>
<thead>
<tr>
<th>Index</th>
<th>Actor Name</th>
<th>Character Name</th>
<th>Gender</th>
<th>Status</th>
</tr>
</thead>
<tbody>
<tr *ngFor=“let character of characters; let i = index”>
<td>{{ i+1 }}</td>
<td>{{ character.actor_name }}</td>
<td>{{ character.character_name }}</td>
<td>{{ character.gender }}</td>
<td>{{ character.status }}</td>
</tr>
</tbody>
</table>
</div>

So, we can add the i as a local variable and display inside the columns using the below code.

<tr *ngFor=“let character of characters; let i = index”>
<td>{{ i+1 }}</td>

In the output, we can see the Index, which starts from 1.

Step 4: How to stripe a table using even and odd

NgForOf provides exported values that can be aliased to local variables.

The following exported values can be aliased to local variables.

  1. $implicit: T: The value of all the individual items in the iterable (ngForOf).
  2. ngForOfNgIterable<T>: The value of an iterable expression. Useful when the expression is more complicated then property access, for example when using the async pipe (userStreams | async).
  3. index: number: An index of the current item in the iterable.
  4. first: boolean: True when an item is the first item in the iterable.
  5. last: boolean: True when an item is the last item in the iterable.
  6. even: boolean: True when an item has an even index in the iterable.
  7. odd: boolean: True when an item has an odd index in the iterable.

Now, we use even and odd local variables to differentiate the rows of the table.

We use the NgClass conditional directive. Write the following code inside the app.component.css file. We will define two classes 1) even 2) odd. Then we use those classes based on the even and odd local variable inside the ngFor directive.

.odd {
background-color: beige;
}
.even {
background-color: aquamarine;
}

Now, write the following code inside the app.component.html file.

<!-- app.component.html -->

<div class=“container”>
<table class=“table table-responsive”>
<thead>
<tr>
<th>Index</th>
<th>Actor Name</th>
<th>Character Name</th>
<th>Gender</th>
<th>Status</th>
</tr>
</thead>
<tbody>
<tr *ngFor=“let character of characters;
let i = index;
let even = even;
let odd = odd”
[ngClass]=“{ odd: odd, even: even }”>
<td>{{ i }}</td>
<td>{{ character.actor_name }}</td>
<td>{{ character.character_name }}</td>
<td>{{ character.gender }}</td>
<td>{{ character.status }}</td>
</tr>
</tbody>
</table>
</div>

In the above code, see the ngFor directive, we have used the local variables like odd and even. Then we have used the ngClass directive to assign the different classes based on the odd and even values.

Save the file and see the output.

 

Step 5: Identifying the first and the last row of a table

We have seen the odd and even. Now, see the first and last element.

First, define the two classes inside the app.component.css file.

.first {
background-color: blanchedalmond;
}
.last {
background-color: cadetblue;
}

Now, write the following code inside the app.component.html file.

<!-- app.component.html -->

<div class=“container”>
<table class=“table table-responsive”>
<thead>
<tr>
<th>Index</th>
<th>Actor Name</th>
<th>Character Name</th>
<th>Gender</th>
<th>Status</th>
</tr>
</thead>
<tbody>
<tr *ngFor=“let character of characters;
let i = index;
let first = first;
let last = last”
[ngClass]=“{ first: first, last: last }”>
<td>{{ i }}</td>
<td>{{ character.actor_name }}</td>
<td>{{ character.character_name }}</td>
<td>{{ character.gender }}</td>
<td>{{ character.status }}</td>
</tr>
</tbody>
</table>
</div>

So, now it will change the background color of the first and last row. See the output below.

 

Finally, the Angular NgFor Tutorial With Example | NgForOf Directive is over.

Originally published by Krunal at appdividend.com

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

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

Learn More

☞ Angular 8 (formerly Angular 2) - The Complete Guide

☞ Complete Angular 8 from Zero to Hero | Get Hired

☞ Learn and Understand AngularJS

☞ The Complete Angular Course: Beginner to Advanced

☞ Angular Crash Course for Busy Developers

☞ Angular Essentials (Angular 2+ with TypeScript)

☞ Angular (Full App) with Angular Material, Angularfire & NgRx

☞ Angular & NodeJS - The MEAN Stack Guide




#angular #web-development

What is GEEK

Buddha Community

Angular NgFor Tutorial With Example | NgForOf Directive
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

Clara  Gutmann

Clara Gutmann

1598731020

Angular NgFor Example | NgForOf Directive in Angular 9

Angular NgFor is a structural directive that renders the template for each item in the collection. The ngForOf is generally used in the shorthand form *ngFor. The core directive ngFor allows us to build data presentation lists and tables in our HTML templates. When we need to  display data in Angular, we use the ngFor directive.

Angular NgFor Example

NgFor is an inbuilt template directive that makes it easy to iterate over something like an array or an object and create a template for each item. You can also set local variables for the following exported values: index, first, last, even, and odd. the index will return the current loop index and the other values by providing a boolean indicating if the value is true or false.

Let’s see the Syntax of the** NgFor directive.**

<ng-template *ngFor="let item of items; index as i; trackBy: trackByFn">...</ng-template>

Let’s take an example of the ngFor directive in Angular.

#angular #angular 9 #angular ngfor

I am Developer

1610191977

Angular 11 Google Social Login Example Tutorial

Angular 9/10/11 social login with google using angularx-social-login library example. In this tutorial, i will show you step by step on how to implement google social login in angular 11 app.

And also, this tutorial will show you How to login into Angular 10/11 application with google using angularx-social-login library in angular 11 app.

Google Login Integration In Angular 11 App

  • Step 1 - Create New Angular App
  • Step 2 - Install Social Login Library
  • Step 3 - Add Code on App.Module.ts File
  • Step 4 - Add Code on View File
  • Step 5 - Add Code On App.Component ts File
  • Step 6 - Start the Angular Google Login App

https://www.tutsmake.com/angular-11-google-social-login-example/

#angular 11 google login #angular 11 social-login example #login with google button angular 8/9/10/11 #angular 10/11 login with google #angular 10 social google login #angular social login google

Roberta  Ward

Roberta Ward

1593184320

Basics of Angular: Part-1

What is Angular? What it does? How we implement it in a project? So, here are some basics of angular to let you learn more about angular.

Angular is a Typescript-based open-source front-end web application platform. The Angular Team at Google and a community of individuals and corporations lead it. Angular lets you extend HTML’s syntax to express your apps’ components clearly. The angular resolves challenges while developing a single page and cross-platform applications. So, here the meaning of the single-page applications in angular is that the index.html file serves the app. And, the index.html file links other files to it.

We build angular applications with basic concepts which are NgModules. It provides a compilation context for components. At the beginning of an angular project, the command-line interface provides a built-in component which is the root component. But, NgModule can add a number of additional components. These can be created through a template or loaded from a router. This is what a compilation context about.

What is a Component in Angular?

Components are key features in Angular. It controls a patch of the screen called a view. A couple of components that we create on our own helps to build a whole application. In the end, the root component or the app component holds our entire application. The component has its business logic that it does to support the view inside the class. The class interacts with the view through an API of properties and methods. All the components added by us in the application are not linked to the index.html. But, they link to the app.component.html through the selectors. A component can be a component and not only a typescript class by adding a decorator @Component. Then, for further access, a class can import it. The decorator contains some metadata like selector, template, and style. Here’s an example of how a component decorator looks like:

@Component({
    selector: 'app-root',
    templateUrl: 'app.component.html',
    styleUrls: ['app.component.scss']
})

Role of App Module

Modules are the package of functionalities of our app. It gives Angular the information about which features does my app has and what feature it uses. It is an empty Typescript class, but we transform it by adding a decorator @NgModule. So, we have four properties that we set up on the object pass to @NgModule. The four properties are declarations, imports, providers, and bootstrap. All the built-in new components add up to the declarations array in @NgModule.

@NgModule({
declarations: [
  AppComponent,
],
imports: [
  BrowserModule,
  HttpClientModule,
  AppRoutingModule,
  FormsModule
],
bootstrap: [AppComponent]
})

What is Data Binding?

Data Binding is the communication between the Typescript code of the component and the template. So, we have different kinds of data binding given below:

  • When there is a requirement to output data from our Typescript code in the HTML template. String interpolation handles this purpose like {{data}} in HTML file. Property Binding is also used for this purpose like [property] = “data”.
  • When we want to trigger any event like clicking a button. Event Binding works while we react to user events like (event) = “expression”.
  • When we can react to user events and output something at the same time. Two-way Binding is used like [(ngModel)] = “data”.

image for understanding data binding

#angular #javascript #tech blogs #user interface (ui) #angular #angular fundamentals #angular tutorial #basics of angular

akshay L

akshay L

1613737472

Angular Tutorial | Angular Tutorial For Beginners | Angular Training | Intellipaat

In this Angular tutorial you will learn what is angular, angular architecture, what is typescript, Data binding & interpolation, angular components, Variable Declaration & Function Declaration, Encapsulation & Polymorphism in Angular, Angular Routing and Navigation, various angular basic & advanced concepts, hands-on demo on how to import & export data in angular, Angular JS vs Angular vs React JS and angular CLI among others.

#angular tutorial #angular tutorial for beginners #angular training