本篇文章和大家一起聊聊angular9中攔截器的使用。有一定的參考價(jià)值，有需要的朋友可以參考一下，希望對(duì)大家有所幫助。

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攔截器統(tǒng)一添加token

我們?cè)谧鲆粋€(gè)后臺(tái)管理系統(tǒng)時(shí),需要給每個(gè)請(qǐng)求的請(qǐng)求頭里面添加token,所以下面我們來(lái)了解一下angular的攔截器,并使用

攔截器使用

1.創(chuàng)建http.service.ts,用于網(wǎng)絡(luò)請(qǐng)求

import { Injectable } from '@angular/core';import { HttpClient } from '@angular/common/http';@Injectable({   providedIn: 'root'})export class HttpService {    constructor(private http: HttpClient) { }   getData () {     return this.http.get('/assets/mock/data.json')   }}

2.創(chuàng)建noop.interceptor.ts,攔截器實(shí)現(xiàn)代碼

import { Injectable } from '@angular/core';import {   HttpEvent, HttpInterceptor, HttpHandler, HttpRequest, HttpResponse} from '@angular/common/http';import { Observable } from 'rxjs';import { tap } from 'rxjs/operators';import { Router } from '@angular/router';/** Pass untouched request through to the next request handler. */@Injectable()export class NoopInterceptor implements HttpInterceptor {     constructor (private router: Router) {}   intercept(req: HttpRequest<any>, next: HttpHandler):     Observable<HttpEvent<any>> {     // 攔截請(qǐng)求,給請(qǐng)求頭添加token     let url = req.url // 可以對(duì)url進(jìn)行處理     let token = document.cookie && document.cookie.split("=")[1]     // 登錄請(qǐng)求排除在外     // if (!url.includes('login')) {         req = req.clone({             url, // 處理后的url,再賦值給req             headers: req.headers.set('Authorization', token)//請(qǐng)求頭統(tǒng)一添加token         })     // }     return next.handle(req).pipe(         tap(          event => {           if (event instanceof HttpResponse) {            console.log(event);            if (event.status >= 500) {             // 處理錯(cuò)誤            }           }          },          error => {           // token過(guò)期 服務(wù)器錯(cuò)誤等處理         //   this.router.navigate(['/login']);          })        );   }}

3.在app.module.ts中使用

3.1imports中引入HttpClientModule

3.2HttpService的注冊(cè)

3.3NoopInterceptor攔截器的使用

import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';import { HttpService } from './auth/http.service';import { NoopInterceptor } from './auth/noop.interceptor';@NgModule({    imports: [       BrowserModule,       HttpClientModule,       AppRoutingModule   ],    providers: [       HttpService,       { provide: HTTP_INTERCEPTORS, useClass: NoopInterceptor, multi: true }    ],    // ... 省略})

攔截器實(shí)現(xiàn)后的效果

攔截器一般配合路由守衛(wèi)一起使用。