Description
The component's view can be defined by using the template which tells Angular how to display the component. The template describes how the component is rendered on the page.Example
The below example describes use of template in the Angular 2:<!DOCTYPE html> <html> <head> <title>Angular 2 Template</title> <script src="https://cdnjs.cloudflare.com/ajax/libs/es6-shim/0.33.3/es6-shim.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.20/system-polyfills.js"></script> <script src="https://code.angularjs.org/2.0.0-beta.6/angular2-polyfills.js"></script> <script src="https://code.angularjs.org/tools/system.js"></script> <script src="https://code.angularjs.org/tools/typescript.js"></script> <script src="https://code.angularjs.org/2.0.0-beta.6/Rx.js"></script> <script src="https://code.angularjs.org/2.0.0-beta.6/angular2.dev.js"></script> <script> System.config({ transpiler: 'typescript', typescriptOptions: { emitDecoratorMetadata: true }, packages: {'app': {defaultExtension: 'ts'}}, map: { 'app': './angular2/src/app' } }); System.import('app/template_main') .then(null, console.error.bind(console)); </script> </head> <body> <my-app>Loading...</my-app> </body> </html>The above code includes the following configuration options:
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You can configure the index.html file using typescript version. The SystemJS transpile the TypeScript to JavaScript before running the application by using the transpiler option.
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If you do not transpile to JavaScript before running the application, you could see the compiler warnings and errors which are hidden in the browser.
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The TypeScript generates metadata for each and every class of the code when the emitDecoratorMetadata option is set. If you don't specify this option, large amount of unused metadata will be generated which affects the file size and impact on the application runtime.
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Angular 2 includes the packages form the app folder where files will have the .ts extension.
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Next it will load the main component file from the app folder. If there is no main component file found, then it will display the error in the console.
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When Angular calls the bootstrap function in main.ts, it reads the Component metadata, finds the 'app' selector, locates an element tag named app, and loads the application between those tags.
template_main.ts
import {bootstrap} from "angular2/platform/browser" //importing bootstrap function import {MyTemplate} from "./template_app.component" //importing component function bootstrap(MyTemplate);Now we will create a component in TypeScript(.ts) file which we will create component and view for the component.
template_app.component.ts
// component's metadata can be accessed using this primary Angular library import {Component, View} from "angular2/core"; //framework recognizes @Component annotation and knows that we are trying to create a new component @Component({ selector: 'my-app' //specifies selector for HTML element named 'app' }) @View({ //template property holds component's companion template that tells Angular how to render a view template: '<h2>Welcome to the world of {{val}}</h2>' }) export class MyTemplate { val : 'Tutorialspoint!!!' }
Output
When you run the above code, it will display the text specified within the template option which is defined in the template_app.component.ts file and holds component's companion template that tells Angular how to render a view.Let's carry out the following steps to see how above code works:
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Save above HTML code as index.html file as how we created in environment chapter and use the above app folder which contains .ts files.
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Open the terminal window and enter the below command:
npm start -
After few moments, a browser tab should open and displays the output as shown below.
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Save above HTML code as angular2_templates.html file in your server root folder.
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Open this HTML file as http://localhost/angular2_templates.html and output as below gets displayed.
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