Angular 8订阅拦截器中的可观测对象

import { Injectable } from '@angular/core';
import { HttpInterceptor, HttpRequest, HttpHandler, HttpEvent } from '@angular/common/http';
import { Observable } from 'rxjs';

@Injectable()
export class MyInterceptor implements HttpInterceptor {
  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    // 在请求发送前执行的逻辑
    console.log('请求发送前');

    // 修改请求头
    const modifiedRequest = request.clone({
      setHeaders: {
        Authorization: 'Bearer token'
      }
    });

    // 继续发送修改后的请求
    return next.handle(modifiedRequest).pipe(
      tap(event => {
        // 在响应返回后执行的逻辑
        console.log('响应返回后');
      }),
      catchError(error => {
        // 处理错误
        console.error('请求错误', error);
        throw error;
      })
    );
  }
}