Angular Components
Definition: Angular components are the building blocks of an Angular application. They control a portion of the user interface and manage the logic for displaying data and handling user interactions.

Structure:

Component Class: Contains the logic and data for the component. It is defined using a TypeScript class.
Component Decorator: Uses the @Component decorator to provide metadata about the component, such as its selector, template URL, and style URLs.
Metadata Properties:

selector: The custom HTML tag that represents the component.
templateUrl: The path to the component's HTML template.
styleUrls: The paths to the component's CSS styles.

Example

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

@Component({
  selector: 'app-user-profile',
  templateUrl: './user-profile.component.html',
  styleUrls: ['./user-profile.component.css']
})
export class UserProfileComponent {
  user = {
    name: 'John Doe',
    email: 'john.doe@example.com'
  };

  updateUser() {
    // Logic to update user information
  }
}

Angular Templates
Definition: Templates in Angular define the view or the UI of a component. They are written in HTML and can include Angular-specific syntax for binding data and handling user events.

Role:

Data Binding: Connects the component's data to the HTML. There are four types of data binding.

Interpolation: Display component properties in the template ({{ property }}).
Property Binding: Bind HTML element properties to component properties ([property]="expression").
Event Binding: Listen for and respond to user events ((event)="expression").
Two-Way Binding: Combine property and event binding for form elements ([(ngModel)]="property").

Directives: Angular templates can use directives to manipulate the DOM. There are structural directives like *ngIf and *ngFor for conditional rendering and iteration.

Example: html

<div class="user-profile">
  <h2>{{ user.name }}</h2>
  <p>Email: {{ user.email }}</p>
  <button (click)="updateUser()">Update Profile</button>
</div>

Role in Building Angular Applications

Modularity: Components allow for modular development, making it easy to break down the application into manageable, reusable pieces.
Separation of Concerns: By separating the logic (component class) from the presentation (template), Angular promotes clean and maintainable code.
Reusability: Components can be reused throughout the application, reducing duplication and simplifying maintenance.
Testability: Components, being self-contained units, are easier to test individually.
Together, components and templates form the core of Angular applications, enabling developers to create dynamic, interactive, and maintainable user interfaces.

Angular Components and Templates