我已经被这个难住了好几个小时了。是时候让你们中的一个人告诉我我做错了什么:)
以下组件失败并显示“没有 TemplateRef 的提供者!”。 plunker 可用 here 。我从 here 得到了 ngSwitch 语法。
import {Component} from '@angular/core'
//This should make the NgSwitch family available, right?
import {CORE_DIRECTIVES} from '@angular/common'
// I get same result with explicit import
// import {NgSwitch,NgSwitchWhen} from '@angular/common'
@Component({
selector: 'my-app',
providers: [],
template: `
<div>
<h2>Hello {{name}}</h2>
<div [ngSwitch]="switchValue">
<div ngSwitchWhen="42">It's 42!</div>
<div ngSwitchWhen="21">It's 21!</div>
</div>
</div>
`,
directives: [CORE_DIRECTIVES]
// directives: [NgSwitch,NgSwitchWhen]
})
export class App {
switchValue = 42;
constructor() {
this.name = 'Angular2 (Release Candidate!)'
}
}
最佳答案
如果您使用带有隐式 <template>
的简短语法,则需要添加 *
@Component({
selector: 'my-app',
providers: [],
template: `
<div>
<h2>Hello {{name}}</h2>
<div [ngSwitch]="switchValue">
<div *ngSwitchCase="42">It's 42!</div>
<div *ngSwitchCase="21">It's 21!</div>
<!-- before RC.2
<div *ngSwitchWhen="42">It's 42!</div>
<div *ngSwitchWhen="21">It's 21!</div>
-->
</div>
</div>
`,
})
export class App {
switchValue = 42;
constructor() {
this.name = 'Angular2 (Release Candidate!)'
}
}
另见 NgSwitch directive
关于typescript - Angular2 (2.0.0-beta.17) NgSwitchWhen 给出 "No provider for TemplateRef!",我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/37045941/