1.创建服务：

InterceptorService.ts

　　

import { Injectable } from '@angular/core';
import { HttpEvent,HttpInterceptor,HttpHandler,HttpRequest,HttpResponse} from "@angular/common/http";
import {Observable} from "rxjs/Observable";
import { ErrorObservable } from 'rxjs/observable/ErrorObservable';
import { catchError } from 'rxjs/operators';
import { mergeMap } from 'rxjs/operators';
@Injectable()
export class InterceptorService implements HttpInterceptor{intercept(req:HttpRequest<any>,next:HttpHandler):Observable<HttpEvent<any>>{const authReq = req.clone({url: (req.url + '&token=ujusaruu19')  //对任意请求的url添加token参数});return next.handle(authReq).pipe(mergeMap((event: any) => {if (event instanceof HttpResponse && event.status != 200) {return ErrorObservable.create(event);}return Observable.create(observer => observer.next(event)); //请求成功返回响应}),catchError((res: HttpResponse<any>) => {   //请求失败处理switch (res.status) {case 401:break;case 200:console.log('业务错误');break;case 404:break;case 403:console.log('业务错误');break;}return ErrorObservable.create(event);}));}
}

　　2.导入提供器中，app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';import { AppComponent } from './app.component';
import {InterceptorService} from "./interceptor.service";
import {HTTP_INTERCEPTORS, HttpClientModule} from "@angular/common/http";
import { TestComponent } from './test/test.component';@NgModule({declarations: [AppComponent,TestComponent],imports: [BrowserModule,HttpClientModule],providers: [{provide:HTTP_INTERCEPTORS,useClass:InterceptorService,multi:true}],bootstrap: [AppComponent]
})
export class AppModule { }

　　3.结束，在组件中使用httpClient请求会自动拦截，拦截处理在InterceptorService.ts操作