angular-docs-cn/modules/playground/src/hello_world/index.ts

63 lines
2.3 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {Component, Directive, ElementRef, Injectable, NgModule, Renderer} from '@angular/core';
import {BrowserModule} from '@angular/platform-browser';
import {platformBrowserDynamic} from '@angular/platform-browser-dynamic';
export function main() {
platformBrowserDynamic().bootstrapModule(ExampleModule);
}
// A service available to the Injector, used by the HelloCmp component.
@Injectable()
export class GreetingService {
greeting: string = 'hello';
}
// Directives are light-weight. They don't allow new
// expression contexts (use @Component for those needs).
@Directive({selector: '[red]'})
export class RedDec {
// ElementRef is always injectable and it wraps the element on which the
// directive was found by the compiler.
constructor(el: ElementRef, renderer: Renderer) {
renderer.setElementStyle(el.nativeElement, 'color', 'red');
}
}
// Angular 2.0 supports 2 basic types of directives:
// - Component - the basic building blocks of Angular 2.0 apps. Backed by
// ShadowDom.(http://www.html5rocks.com/en/tutorials/webcomponents/shadowdom/)
// - Directive - add behavior to existing elements.
@Component({
// The Selector prop tells Angular on which elements to instantiate this
// class. The syntax supported is a basic subset of CSS selectors, for example
// 'element', '[attr]', [attr=foo]', etc.
selector: 'hello-app',
// These are services that would be created if a class in the component's
// template tries to inject them.
viewProviders: [GreetingService],
// Expressions in the template (like {{greeting}}) are evaluated in the
// context of the HelloCmp class below.
template: `<div class="greeting">{{greeting}} <span red>world</span>!</div>
<button class="changeButton" (click)="changeGreeting()">change greeting</button>`
})
export class HelloCmp {
greeting: string;
constructor(service: GreetingService) { this.greeting = service.greeting; }
changeGreeting(): void { this.greeting = 'howdy'; }
}
@NgModule({declarations: [HelloCmp, RedDec], bootstrap: [HelloCmp], imports: [BrowserModule]})
class ExampleModule {
}