Angular 12 ngx-translate / loader 无法工作

Question

https://www.npmjs.com/package/@ngx-translate/core https://www.npmjs.com/package/@ngx-translate/http-loader 我从这里安装了翻译包，并添加了 ngx-translate 模块及其 forRoot ，组件 ts（应用程序和标头）内的翻译服务，但它也不起作用

标题组件

<header>
<nav class="navbar navbar-expand-lg navbar-light" id="header">
    <div class="container">
      
      <a class="navbar-brand" href="#">
        <img src=".." alt="logo">
      </a>
      <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
        <span class="navbar-toggler-icon"></span>
      </button>
      <div class="collapse navbar-collapse" id="navbarSupportedContent">
        <ul class="navbar-nav me-auto mb-2 mb-lg-0">
          <li class="nav-item" [routerLinkActive]="['active']" [routerLinkActiveOptions]="{ exact: true }">
           
            <a [routerLink]="['home']" class="nav-link">Home</a>

          </li> 
        
          <li class="nav-item dropdown" [routerLinkActive]="['active']" [routerLinkActiveOptions]="{ exact: true }">
            <a class="nav-link dropdown-toggle"  id="navbarDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false">
              page 2
            </a>
            <ul class="dropdown-menu" aria-labelledby="navbarDropdown">
              <li><a class="dropdown-item" [routerLink]="['page']">page</a></li>
            </ul>
          </li>

          <li class="nav-item" [routerLinkActive]="['active']" [routerLinkActiveOptions]="{ exact: true }">
            <a class="nav-link" [routerLink]="['features']">Features</a>
          </li>
  
          <li class="nav-item" [routerLinkActive]="['active']" [routerLinkActiveOptions]="{ exact: true }">
            <a class="nav-link reserve-btn" [routerLink]="['reserve']">Reserve</a>
          </li>

        </ul>
     
      </div>
<button (click)="translate.use('en')">
  En
</button>

<button (click)="translate.use('ar')">
  Ar
</button>
      
  </div>
  </nav>
</header>

Header.component.ts

import { DOCUMENT } from '@angular/common';
import { Component, HostListener, Inject, OnInit } from '@angular/core';
import { TranslateService } from '@ngx-translate/core';

@Component({
  selector: 'app-header',
  templateUrl: './header.component.html',
  styleUrls: ['./header.component.scss'],
})

export class HeaderComponent implements OnInit {
  // lang: string;

  constructor(@Inject(DOCUMENT) private document: Document,public translate:TranslateService) {}
 
  
  ngOnInit(): void {
    
    // this.lang = localStorage.getItem('lang') || 'en';
  }


}

app.module.ts

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';

import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { GeneralPagesModule } from './general-pages/general-pages.module';
import { RentalPageModule } from './rental-page/rental-page.module';
import { SharedModule } from './shared/shared.module';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import { TranslateModule, TranslateLoader } from '@ngx-translate/core';
import { TranslateHttpLoader } from '@ngx-translate/http-loader';

import { HttpClientModule, HttpClient, HTTP_INTERCEPTORS } from '@angular/common/http';

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

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    SharedModule,
    GeneralPagesModule,
    RentalPageModule,
    BrowserAnimationsModule,
    // TranslateModule,
     HttpClientModule,
    TranslateModule.forRoot({
      defaultLanguage:'en',
      loader: {
        provide: TranslateLoader,
        useFactory: createTranslateLoader,
        deps: [HttpClient]
      }
    }),
  ],
  providers: [
    // { provide: HTTP_INTERCEPTORS, useClass: HttpInterceptorService, multi: true },

  ],
  bootstrap: [AppComponent]
})
export class AppModule { }

export function createTranslateLoader(http:HttpClient){
  return new TranslateHttpLoader(http,'./assets/i18n/','.json')
}

我也在 app.component.ts 中尝试了相同的步骤

import { Component, Inject } from '@angular/core';
import * as AOS from 'aos';
import { DOCUMENT } from '@angular/common';
import { TranslateService } from '@ngx-translate/core';
import { ActivatedRoute, NavigationEnd, Router } from '@angular/router';
import { filter} from 'rxjs/operators';



@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent {
  ngOnInit(){
    AOS.init({
      duration: 1200,
    });
    }


  // Inject document which is safe when used with server-side rendering
  constructor(@Inject(DOCUMENT) private document: Document,public translate:TranslateService,
  private router: Router, private route: ActivatedRoute) {

   
  }


}

in home.compoent.html

{{"HOME" || translate}}

home.compoent.ts

import { Component, OnInit } from '@angular/core';
import { TranslateService } from '@ngx-translate/core';

@Component({
  selector: 'app-home',
  templateUrl: './home.component.html',
  styleUrls: ['./home.component.scss']
})
export class HomeComponent implements OnInit {

  constructor(public translate:TranslateService) { }

  ngOnInit(): void {
  }

}

Answer 1

管道语法是

{{ 'my-translation-key' | translate }}

- 你有两个 ||在您的模板中，请更改并重试。

或者，如果您需要在控制器中设置变量，您可以注入翻译服务并使用

myTanslation = this.translateService.instant('my-translation-key')

。

Answer 2

我面临同样的问题，但没有任何效果，我尝试了所有方法，这是 Angular/core12.0.0 的问题。我在其中浪费了3天时间。它在角度 11 中工作正常，但在角度 12 中没有。因此创建自定义管道。 :)

import { Pipe, PipeTransform } from '@angular/core';
import { TranslatePipe } from "@ngx-translate/core";

@Pipe({
  name: 'myTranslate',
  pure: false
})

export class MyTranslate extends TranslatePipe implements PipeTransform {
  transform(value: any, args?: any[]): any {
    return super.transform(value, args)
  }
} 
 {{ myvalue | myTranslate } 

Answer 3

我也面临着类似的问题，经过一些调试，我发现（也许是假设）对于延迟加载的模块，翻译的提供速度不够快，无法在 HTML 中提供。证明是，如果您在 TS 中获得翻译或调用一个函数来通过 TS 函数，或者如果您在 HTML 中添加一个条件，该条件在几秒钟后为 true，那么翻译将正常工作。 我想出了以下两种解决方案。

1. 首先是在相关的forChild中加载TranslateModule 延迟加载模块。
2. 第二个是添加 TranslateService(@ngx-translate/core) 到 延迟加载模块的提供者数组。 我希望这对面临类似问题的人有所帮助。