Angular Expressions

Angular expressions are used to bind data to HTML. They are similar to JavaScript expressions, but they are evaluated by Angular within the context of the Angular framework. This tutorial covers the basics of Angular expressions and how to use them effectively in your templates.

What are Angular Expressions?

Angular expressions are code snippets that are evaluated within the context of the Angular framework. They are used to bind data from your component's class to the view, allowing you to create dynamic and interactive user interfaces.

Basic Usage of Angular Expressions

Angular expressions are written inside double curly braces {{ }}. Here is a simple example:

<p>{{ title }}</p>

export class AppComponent {
  title = 'Hello, Angular!';
}

Using Expressions in Templates

Angular expressions can be used in various parts of your templates, such as inside element content, attribute values, and bindings.

Element Content

<p>{{ description }}</p>

export class AppComponent {
  description = 'This is a description text.';
}

Attribute Values

<img [src]="imageUrl" alt="{{ imageAlt }}">

export class AppComponent {
  imageUrl = 'https://example.com/image.jpg';
  imageAlt = 'Example Image';
}

Bindings

<button (click)="showMessage()">{{ buttonText }}</button>

export class AppComponent {
  buttonText = 'Click me';

  showMessage() {
    console.log('Button clicked!');
  }
}

Expressions with Functions and Methods

You can use expressions to call functions and methods defined in your component class.

<p>{{ getTitle() }}</p>

export class AppComponent {
  title = 'Hello, Angular!';

  getTitle() {
    return this.title;
  }
}

Expressions with Built-in Angular Features

Angular expressions can be combined with built-in Angular features, such as pipes, to format data.

<p>{{ today | date:'fullDate' }}</p>

export class AppComponent {
  today = new Date();
}

Key Points

Conclusion

Angular expressions are a powerful tool for binding data to your templates and creating dynamic user interfaces. By understanding and using Angular expressions effectively, you can enhance the interactivity and functionality of your Angular applications. Happy coding!