angular6 - 如何使用 Angular 7 创建 2 分钟倒数计时器？

Question

我不会创建 2 分钟倒数计时器。我也尝试了这段代码，但它是秒任何人请告诉我如何使用创建 2 分钟倒计时计时器angular 7 (typescript)

timer() {

   this.countdown().subscribe(
     t => {
       this.value1 = t
     },
     null,
     () => {

     }
   );
   this.start(60);
 }

// 60 秒计数代码

 countdown(): Observable<number> {
   return this._countdown.asObservable();
 }

 private isCounting = false;
 start(count: number): void {
   if (!this.isCounting) {
     this.isCounting = true;
     timer(0, 1000).pipe(
       takeWhile(t => t < count),
       map(t => count - t)
     ).subscribe(
       t => this._countdown.next(t),
       null,
       () => {
         this._countdown.complete();
         this.isCounting = false;
         this._countdown = new Subject<number>();
       }
     );
   }
 } 

标签： angular6