Question

关于这条链的完成，我想展示val3乘以val5的结果。

现在这是我的模拟服务结构：

{
  "person": [{
    "val1": 1,
    "val2": 2
  }],
  "facility": [{
    "val3": 3,
    "val4": 4
  }],
  "exposure": [{
    "val5": 5
  }]
}

这是组件，我在其中调用服务。

import { Injectable } from '@angular/core';
import { Person } from './entities/person';
import { HttpClient } from '@angular/common/http';
import { Observable } from '../../node_modules/rxjs/Observable';

@Injectable()
export class DataService {

  apiUrl1: string = 'http://localhost:3000/person/?';
  apiUrl2: string = 'http://localhost:3000/facility/?';
  apiUrl3: string = 'http://localhost:3000/exposure/?';

  constructor(private http: HttpClient) {
  }

  getData(arg): Observable<any> {
    return (this.http.get(this.apiUrl1 + arg)
      .flatMap((response: any) => this.http.get(this.apiUrl2 + response.val1))
      .flatMap((response: any) => this.http.get(this.apiUrl3 + response.val2))
      )
  }

}

Answer 1

我想这就是你想要的？（Rxjs使用pipe（）方法）。您只需要将值乘以所需的值即可将响应映射为输出。

getData(arg): Observable<any> {
  return this.http.get(this.apiUrl1 + arg).pipe(
    flatMap((response: any) => this.http.get(this.apiUrl2 + response.val1)),
    flatMap((response: any) => this.http.get(this.apiUrl3 + response.val2)),
    map((response: any) => response.val3 * response.val5)
  )
}

请注意，这只会返回一个数字。因此，如果您还需要其他方式的响应，请订阅它：

constructor(private http: HttpClient) {
  this.getData(arg).subscribe(result => {
    const output = result.val3 * response.val5;
  });
}

getData(arg): Observable<any> {
  return this.http.get(this.apiUrl1 + arg).pipe(
    flatMap((response: any) => this.http.get(this.apiUrl2 + response.val1)),
    flatMap((response: any) => this.http.get(this.apiUrl3 + response.val2))
  )
}

乘以来自不同Web服务调用的响应

1 个答案: