在Angular 2中截取HTTP响应

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

@Injectable()
export class MyInterceptor implements HttpInterceptor {
  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    // 在请求头中添加自定义信息
    const modifiedRequest = request.clone({
      setHeaders: {
        'X-Custom-Header': 'Custom Value'
      }
    });

    // 发送修改后的请求到下一个拦截器或服务器
    return next.handle(modifiedRequest).pipe(
      map(response => {
        // 对响应进行转换
        const modifiedResponse = response.clone({
          body: response.body + ' (Modified)'
        });
        return modifiedResponse;
      }),
      catchError(error => {
        // 处理错误
        console.error('An error occurred:', error);
        throw error;
      })
    );
  }
}

import { HTTP_INTERCEPTORS } from '@angular/common/http';

@NgModule({
  providers: [
    {
      provide: HTTP_INTERCEPTORS,
      useClass: MyInterceptor,
      multi: true
    }
  ]
})
export class AppModule { }