deepthan / blog-angular

Angular 笔记
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AsyncPipe #81

Open deepthan opened 4 years ago

deepthan commented 4 years ago

AsyncPipe

官方文档

基本使用方法

{{ obj_expression | async }}

异步管道会监听一个Observable或者promise,并且会使用它返回的最终数据,异步管道使得组件可以对变化进行检测。当组件卸载的时候,异步管道会自动取消监听以避免潜在的内存泄露。

 greeting: Promise<string>|null = null;

 private resolve: Function|null = null;

this.greeting = new Promise<string>((resolve, reject) => { this.resolve = resolve; });
 <span> {{ greeting | async }}</span>