javascript - Angular 组合来自不同方法的数据

Question

我有来自三个不同服务的数据，我想将来自所有服务的数据合并到一个方法中

this.data1 = this.activity1Service.getAllMonth(); 
this.data2 = this.activity2Service.getAllMonth();
this.data3 = this.activity3Service.getAllMonth();

this.alldata =  concat (this.data1,this.data2,this.data3); 

并作为 Observable 调用

GetAllData(): Observable<Data[]>{


  return (this.alldata);

  }

然后也许做 ngOnInit()

ngOnInit() {

    this.dataService.getAllData().subscribe(aldata => this.AllData = aldata);
  } 

我不确定如何将来自不同服务的数据组合成一种方法，请任何人帮忙。

Answer 1

您可以使用forkJoin

forkJoin waits for each HTTP request to complete and group’s all the observables returned by each HTTP call into a single observable array and finally return that observable array.

类文件

getAllData() {
        this.data1 = this.activity1Service.getAllMonth(); 
        this.data2 = this.activity2Service.getAllMonth();
        this.data3 = this.activity3Service.getAllMonth();
        return forkJoin([this.data1, this.data2, this.data3]);
}


ngOnInit() {

    this.getAllData().subscribe(aldata => {
        console.log(data);
        this.AllData = aldata
    });
}