在 Angular 中,拦截器类中的局部变量在 intercept 函数中无法反映更改的问题可以通过使用 RxJS 的 BehaviorSubject 来解决。以下是一个示例解决方法:
InterceptorService
的新服务,并使用以下代码编写该服务:import { Injectable } from '@angular/core';
import { HttpInterceptor, HttpRequest, HttpHandler, HttpEvent } from '@angular/common/http';
import { Observable, BehaviorSubject } from 'rxjs';
@Injectable()
export class InterceptorService implements HttpInterceptor {
private refreshTokenInProgress = new BehaviorSubject(false);
// 提供一个公共方法,用于更改 refreshTokenInProgress 的值
public setRefreshTokenInProgress(value: boolean): void {
this.refreshTokenInProgress.next(value);
}
intercept(req: HttpRequest, next: HttpHandler): Observable> {
// 在拦截器中订阅 refreshTokenInProgress 的变化
this.refreshTokenInProgress.subscribe((refreshTokenInProgress: boolean) => {
// 根据 refreshTokenInProgress 的值执行逻辑
if (refreshTokenInProgress) {
// 如果需要执行某些操作,例如添加请求头等
req = req.clone({
headers: req.headers.set('Authorization', 'Bearer ' + 'refresh_token_here')
});
}
});
return next.handle(req);
}
}
app.module.ts
)中,将 InterceptorService
添加到 providers
数组中:import { NgModule } from '@angular/core';
import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';
import { InterceptorService } from './interceptor.service';
@NgModule({
imports: [
HttpClientModule
],
providers: [
{
provide: HTTP_INTERCEPTORS,
useClass: InterceptorService,
multi: true
}
]
})
export class AppModule { }
InterceptorService
,并调用 setRefreshTokenInProgress
方法来更改 refreshTokenInProgress
的值:import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { InterceptorService } from './interceptor.service';
@Injectable()
export class DataService {
constructor(private http: HttpClient, private interceptorService: InterceptorService) { }
public fetchData(): Observable {
// 在需要更改拦截器中的变量时,调用 setRefreshTokenInProgress 方法
this.interceptorService.setRefreshTokenInProgress(true);
return this.http.get('your_api_url');
}
}
通过这种方式,你可以在拦截器中使用 refreshTokenInProgress
的最新值来执行逻辑操作。