Question

我创建了Angular 5项目并创建了一个工厂，它应该在应用程序启动之前提供服务中的元数据。问题是我收到错误：

RangeError: Maximum call stack size exceeded
    at resolveNgModuleDep (core.js:10559)
    at _callFactory (core.js:10649)
    at _createProviderInstance$1 (core.js:10599)
    at resolveNgModuleDep (core.js:10581)
    at _createClass (core.js:10622)
    at _createProviderInstance$1 (core.js:10596)
    at resolveNgModuleDep (core.js:10581)
    at NgModuleRef_.get (core.js:11806)
    at new MetadataService (metadata.service.ts:23)
    at _createClass (core.js:10622)

应用模块：

@NgModule({
  declarations: [
      AppComponent,
      ...
  ],
  imports: [
      BrowserModule,
      HttpClientModule,
      AppRoutingModule,
      FormsModule,
      FlexLayoutModule,
      I18NextModule.forRoot()
  ],
  providers: [
      { provide: HTTP_INTERCEPTORS, useClass: AuthInterceptor, multi: true },
      MetadataService,
      { provide: APP_INITIALIZER, useFactory: MetadataProviderFactory, deps: [MetadataService], multi: true },
      { provide: APP_INITIALIZER, useFactory: I18NextProviderFactory, deps: [I18NEXT_SERVICE], multi: true }      
  ],
  bootstrap: [AppComponent]
})
export class AppModule { }

元数据服务：

import { Injectable, Injector } from '@angular/core';
import { Observable } from 'rxjs/Observable';
import { HttpClient } from '@angular/common/http';   

@Injectable()
export class MetadataService {   
    private http: HttpClient;

    constructor(private injector: Injector) { 
        this.http = injector.get(HttpClient);  // this row makes a problem
    }

这一行出了问题。

 this.http = injector.get(HttpClient);

我把这行避免循环引用，我得到“超出最大调用堆栈大小”。哪里错了？

Answer 1

您可以通过延迟您在服务初始化上进行的http调用来暂时解决此问题，只需setTimeOut（不需要任何秒数）。我已经浏览了一些开放的Angular线程，主要问题与HttpInterceptor和与HttpClient的循环依赖性有关。

使用进样器时角度“超出最大调用堆栈大小”

1 个答案: