Components and templates

Components and templates are two of the key building blocks of Angular applications. In this article, we’ll take a closer look at what components and templates are, how they work together, and how you can use them to build powerful and interactive web applications.

First, let’s define what we mean by components and templates. In Angular, a component is a class that controls a portion of the user interface. It does this by defining a template, which is a piece of HTML that describes the layout and content of the component’s view. The component is responsible for rendering the template and handling user interactions with the view.

Here’s a simple example of an Angular component:

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

@Component({
  selector: 'app-root',
  template: `
    <h1>Hello, World!</h1>
  `
})
export class AppComponent {
  title = 'my-app';
}

In this example, the component is a class with a decorator (@Component) that specifies the component’s metadata. The metadata includes a selector, which is the name of the HTML element that the component’s template will be rendered in, and a template, which is a piece of HTML that defines the layout and content of the component’s view.

The component class itself (AppComponent in this example) can contain properties and methods that control the behavior of the component. In this case, the component has a property called title that can be used in the template to display dynamic content.

Now let’s look at how the component’s template is used to render the component’s view. When the component is instantiated, Angular will take the template and create a view based on it. The view is a live representation of the template, and it is responsible for rendering the template’s content to the DOM and handling user interactions with the view.

Here’s an example of how you might use the component’s template to display dynamic content:

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

@Component({
  selector: 'app-root',
  template: `
    <h1>{{title}}</h1>
  `
})
export class AppComponent {
  title = 'my-app';
}

In this example, the component’s template uses double curly braces ({{ }}) to bind to the component’s title property. This allows the component to display the value of the title property in the template. When the component’s title property is changed, the template will be automatically updated to reflect the new value.

Components and templates are a powerful combination that allow you to build rich and interactive applications in Angular. By defining components and templates, you can create reusable pieces of UI that can be easily customized and integrated into your application. With the power of Angular’s template syntax and component-based architecture, you can build applications that are fast, efficient, and easy to maintain.