如何在Angular中依次发送多个Http请求

时间:2019-04-29 10:48:01

标签: angular rxjs angular6 angular7

我编写了以下代码,每次在发布请求发生之前调用API, 第一个API被调用,第二个未被调用

  public post(postUrl: string, model: any): Observable<any> {
    return this.validateTokenStatus().pipe(map(response => {
        console.log('response', response);
        // if (response) {
        console.log('response2', response);
        const url = `${environment.webApiUrl}/${postUrl}`;
        this.spinnerService.start();
        console.log('response21', response);
        return this._http.post(url, model).pipe(map((res: any) => {
            console.log('response11', response);
            this.spinnerService.stop();
            return res;
        },
        error => {
            console.log('error');
            return error;
        }));
        // } else {
       // console.log('response3', response);
        // return true;
        // }
    }));
}

1 个答案:

答案 0 :(得分:1)

当您要依次执行多个异步操作时,通常希望使用mergeMap,switchMap或concatMap中的一个。在这种情况下,类似的事情可能会起作用:

return this.validateTokenStatus()
  .pipe(
    switchMap(response => {
        const url = `${environment.webApiUrl}/${postUrl}`;
        this.spinnerService.start();
        return this._http.post(url, model);
    }),
    map((res: any) => {
        this.spinnerService.stop();
        return res;
    })
  );