我正在关注有关Angular翻译的本教程（https://alligator.io/angular/ngx-translate/）。当我在HTML文件中调用翻译时，什么都没有发生，而且我看到一个空行：

  

<label translate='demo.title'></label>

但是在我的component.ts中，如果导入导入{TranslateService} from '@ngx-translate/core';，我可以使用以下方式获得正确的翻译：

title:string;
constructor(private translate: TranslateService) { }
ngOnInit() {

  this.translate.get(['demo.title'])
    .subscribe(translations => {
      this.title = translations['demo.title'];
      console.log(this.title ); // the right translations appears in console
    });
}

app.module.ts

// import ngx-translate and the http loader
import {TranslateLoader,TranslateModule} from '@ngx-translate/core';
import {TranslateHttpLoader} from '@ngx-translate/http-loader';


@NgModule({
  declarations: [AppComponent],imports: [
    BrowserModule,AppRoutingModule,HomeModule,IndexModule,NoPageModule,HttpClientModule,// ngx-translate and the loader module
    TranslateModule.forRoot({
        loader: {
            provide: TranslateLoader,useFactory: HttpLoaderFactory,deps: [HttpClient]
        }
    }),RouterModule.forRoot(routes,{ useHash: true }),],providers: [AuthService,AuthGuard],bootstrap: [AppComponent],schemas:[CUSTOM_ELEMENTS_SCHEMA]
})
export class AppModule {}

// required for AOT compilation
export function HttpLoaderFactory(http: HttpClient) {
  return new TranslateHttpLoader(http);
}

pt.json

{
  "demo": {
    "title": "oi","text": "This is a simple demonstration app for ngx-translate"
  }
}

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