Angular 4拦截器未设置标头

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

@Injectable()
export class HeaderInterceptor implements HttpInterceptor {
  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    // 在请求中设置标头
    const modifiedRequest = request.clone({
      setHeaders: {
        'Content-Type': 'application/json',
        'Authorization': 'Bearer your_token_here'
      }
    });

    return next.handle(modifiedRequest);
  }
}

import { NgModule } from '@angular/core';
import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';

import { HeaderInterceptor } from './header.interceptor';

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