如果启用了http拦截器并修改响应，则Angular - http post ReportProgress返回未定义的事件

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

@Injectable()
export class ProgressInterceptor implements HttpInterceptor {
  intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    // 处理报告进度的事件
    if (req.reportProgress) {
      return next.handle(req).pipe(
        tap(event => {
          if (event instanceof HttpResponse) {
            // 处理报告进度的事件
            if (event.type === 1) {
              console.log('上传进度：', event.total, event.loaded);
            }
          }
        })
      );
    }
    return next.handle(req);
  }
}

import { HTTP_INTERCEPTORS } from '@angular/common/http';
import { ProgressInterceptor } from './progress.interceptor';

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