从服务文件获取值到app.module的最佳方法

Question

我希望导入从服务文件返回的值，例如，服务文件为：

http.service.ts

selectedEnvironment() {
  return "abc";
}

但是如何将这个值放入我的app.module文件中。 有没有首选的方法？

我试过了：

app.module

import { HttpService } from "./http.service";

export function HttpLoaderFactory(httpClient: HttpClient) {
  return new TranslateHttpLoader(httpClient, "./assets/" + HttpService.selectedEnvironment()+"/i18n/", ".json");
}

但是它说“ typeof HttpService类型type上不存在属性selectedEnvironment ”。

Answer 1

如果是角度服务

import { Injectable } from "@angular/core";

@Injectable()
export class YourHttpService {
  constructor() {}

  getEnvironment() {
    return "XYZ";
  }
}

您可以在HttpLoaderFactory中将服务指定为参数。 请确保在您的应用程序模块的deps：[HttpClient，YourHttpService ]和提供程序提供程序：[YourHttpService]中指定了服务名称

export function HttpLoaderFactory(httpClient: HttpClient,httpService:YourHttpService) {
    console.log(httpService.getEnvironment());
  return new TranslateHttpLoader(httpClient);
}

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    HttpClientModule,
    TranslateModule.forRoot({
      loader: {
        provide: TranslateLoader,
        useFactory: HttpLoaderFactory,
        deps: [HttpClient,YourHttpService]
      }
    })
  ],
  providers: [YourHttpService],
  bootstrap: [AppComponent]
})
export class AppModule { }

示例代码https://stackblitz.com/edit/transalate-vvmckq?file=src/app/app.module.ts

Answer 2

在app.module.ts中添加此

 providers: [HttpService]