如何将属性从父组件传递到Angular 2中的子组件的类构造函数?
计算出一半的神秘感,因为属性可以毫无问题地传递给视图.
/client/app.ts
import {Component,View,bootstrap} from 'angular2/angular2';
import {Example} from 'client/example';
@Component({
selector: 'app'
})
@View({
template: `<p>Hello</p>
<example [test]="someAttr"
[hyphenated-test]="someHyphenatedAttr"
[alias-test]="someAlias"></example>
`,directives: [Example]
})
class App {
constructor() {
this.someAttr = "attribute passsed to component";
this.someHyphenatedAttr = "hyphenated attribute passed to component";
this.someAlias = "attribute passed to component then aliased";
}
}
bootstrap(App);
/client/example.ts
import {Component,Attribute} from 'angular2/angular2';
@Component({
selector: 'example',properties: ['test','hyphenatedTest','alias: aliasTest']
})
@View({
template: `
<p>Test: {{test}}</p>
<!-- result: attribute passsed to component -->
<p>Hyphenated: {{hyphenatedTest}}</p>
<!-- result: hyphenated attribute passed to component -->
<p>Aliased: {{alias}}</p>
<!-- result: attribute passed to component then aliased -->
<button (click)="attributeCheck()">What is the value of 'this.test'?</button>
<!-- result: attribute passed to component -->
`
})
/*******************************************************************
* HERE IS THE PROBLEM. How to access the attribute inside the class?
*******************************************************************/
export class Example {
constructor(@Attribute('test') test:string) {
console.log(this.test); // result: undefined
console.log(test); // result: null
}
attributeCheck() {
alert(this.test);
}
}
要重新迭代:
How can I access an attribute inside the child component’s class passed in from the parent component?
Repo
已更新至beta.1
您可以使用ngOnInit
@Component({
selector: 'example',inputs: ['test','alias: aliasTest'],template: `
<p>Test: {{test}}</p>
<!-- result: attribute passsed to component -->
<p>Hyphenated: {{hyphenatedTest}}</p>
<!-- result: hyphenated attribute passed to component -->
<p>Aliased: {{alias}}</p>
<!-- result: attribute passed to component then aliased -->
<button (click)="attributeCheck()">What is the value of 'this.test'?</button>
<!-- result: attribute passed to component -->
`
})
export class Example {
ngOnInit() {
console.log(this.test);
this.attributeCheck();
}
attributeCheck() {
alert(this.test);
}
}