等待订阅在 while 循环中完成其工作（打字稿）

Question

我有一个 while 循环，在 while 循环内我有两个订阅。我怎样才能等他们完成才能继续使用 while 循环？

this.counter = 1;
array[0] = 3;
while(this.counter <= array[0])
    {
        console.log("WHILE: "+this.counter);
        this.ms.getPopular(this.tv, this.counter).subscribe(val => {
            this.afstore.collection("matches").doc(this.id).valueChanges().pipe(take(1)).subscribe((val2: any) => {
                console.log(this.counter);
                if(this.counter == array[0])
                {
                    return;
                }
                //console.log("YES");
                this.counter++;
            });
        });

        this.counter++;
    }

我当前的输出是

WHILE: 1
WHILE: 2
WHILE: 3
4
5
6

但我想要得到的输出是

WHILE: 1
1
2
3

在 while 循环中甚至不需要 this.counter++。如果没有 while 本身，它就会无限运行

Answer 1

使用递归函数代替循环。

this.counter = 0;
this.max = 3;

function subscribe() {
  
  this.ms.getPopular(this.tv, this.counter).subscribe(val => {
    this.afstore.collection("matches").doc(this.id).valueChanges().pipe(take(1)).subscribe((val2: any) => {

      if (this.counter == this.max) {
        return;
      } else {
        this.counter++;
        this.subscribe();
      }

    });
  });
}

等待订阅在 while 循环中完成其工作（打字稿）

Wait for subscribe to finish its job inside while loop (typescript)

javascript

observable

typescript