What is the app.components.ts file in an Angular application?

Overview

Angular is an open-source platform and a JavaScript framework written in TypeScript for building single-page applications. Angular building blocks are components.

The file structure that is created by default in the Angular application components consists of the following files:

• app.components.css
• app.components.html
• app.componen.spec.ts
• app.component.ts
• app.module.ts

We’ll discuss the app.component.ts file in this shot.

Code

Code explanation

• Line 1: The import of the Component class that is defined in the module @angular/core is being done in this line.

• Lines 3-7: The reference to the selector, templateUrl, and styleUrls are given in the declarator. The selector is a tag that is used to be placed in the index.html file.

The Component decorator allows the user to tag a class as an Angular component. Additional information in the metadata determines how the component should be instantiated, processed, and used at the runtime.

• selector identifies the directive in the template and triggers the instantiation of the respective directive.

• templateUrl is the relative or the absolute path of the template file for an Angular component.

• styleUrls are the relative or absolute paths containing CSS stylesheets for the component. There can be one or more URLs in the component decorator.

• Lines 8-10: The AppComponent class has a title variable, which is used to display the application’s title in the browser. In this case, angular will be shown in the browser.