如何合并循环订阅数据angular 2 TS

Question

fieldRender(formSets: any[]) {

    let questions: any[] = [];
    let q: QuestionBase<any>[] = [];
    let index: number = 0;

    formSets.forEach(formSet => {
      formSet.children.forEach(child => {
        this.appointmentService.getField(child.field.uuid).subscribe(res => {
          let dataType;
          let label;
          let parent;
          let uuid;
          let answers = [];

          if (res.concept != null) {
            if (res.concept.datatype)
              dataType = res.concept.datatype.display;
            if (res.answers)
              answers = res.answers;
          }
          uuid = res.uuid;
          label = res.display;
          parent = formSet.parent.field.display;

          let question: Question = new Question();
          question.label = label;
          question.type = dataType;
          question.parent = parent;
          question.uuid = uuid;
          question.answers = answers;

          questions.push(question);

          console.log("Questions", JSON.stringify(questions));
        });
      });
    });

  }

这是我的function.What，我希望这个函数返回可观察到的问题，我可以订阅这些问题，以便在任何地方获取数据。FormSets是包含父数组和子数组的FormSet FormSet数组

Answer 1

如果formSet.children是一个数组，您可以执行类似如下的操作

Rx.Observable.from(formSet.children)
.flatMap((child) => this.appointmentService.getField(child.field.uuid))
.subscribe((question) => questions.push(question))

这样，您就可以将来自getField的所有响应放在一个“流”中。

你没有给我们太多的背景信息，所以我猜;)