Angular 6 – run方法每10秒服务一次

checkData() {
    return this.http.get('my url');
}

ngOnInit() {
    this.myservice.checkdata().subscribe( result => { this.statustext = result } );
}

使用rxjs计时器在启动时调用api请求,然后每隔10秒调用一次api请求.

最好通过使用rxjs来划分和征服.

首先,输入以下内容：

import { timer,Observable,Subject } from 'rxjs';
import { switchMap,takeUntil,catchError } from 'rxjs/operators';

然后添加属性来处理对api的请求：

private fetchData$: Observable<String> = this.myservice.checkdata();

接下来,添加属性以处理时间：

private refreshInterval$: Observable<String> = timer(0,1000)
.pipe(
  // This kills the request if the user closes the component 
  takeUntil(this.killtrigger),// switchMap cancels the last request,if no response have been received since last tick
  switchMap(() => this.fetchData$),// catchError handles http throws 
  catchError(error => of('Error'))
);

最后,如果组件被杀死,则触发kill命令：

ngOnDestroy(){
  this.killtrigger.next();
}

这是一个StackBlitz Demo.