带自定义请求头的Angular 4

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

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

    return next.handle(modifiedRequest);
  }
}

import { NgModule } from '@angular/core';
import { HTTP_INTERCEPTORS } from '@angular/common/http';
import { CustomInterceptor } from './custom-interceptor';

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