Angular 2 HTTP"无法解析'AppService'的所有参数"

Question

我试图将http提供程序导入服务,但是我收到以下错误:

无法解析'AppService'(？)的所有参数.确保所有参数都使用Inject进行修饰或具有有效的类型注释,并且"AppService"使用Injectable进行修饰.

以下是一些代码段:

<script src="~/es6-shim/es6-shim.min.js"></script>
<script src="~/systemjs/dist/system-polyfills.js"></script>

<script src="~/angular2/bundles/angular2-polyfills.js"></script>
<script src="~/systemjs/dist/system.src.js"></script>
<script src="~/rxjs/bundles/Rx.js"></script>
<script src="~/angular2/bundles/angular2.dev.js"></script>
<script src="~/angular2/bundles/http.dev.js"></script>

<!-- 2. Configure SystemJS -->
<script>
    System.config({
        map: { 'rxjs': 'RCO/rxjs' },
        packages: {
            RCO: {
                format: 'register',
                defaultExtension: 'js'
            },
            'rxjs': {defaultExtension: 'js'}
        }
    });
  System.import('RCO/Areas/ViewOrganization/AngularTemplates/boot')
      .then(null, console.error.bind(console));

boot.ts

import {bootstrap} from 'angular2/platform/browser'
import {HTTP_PROVIDERS} from 'angular2/http'
import 'rxjs/add/operator/map'
import {AppComponent} from  'RCO/Areas/ViewOrganization/AngularTemplates/app.component'
import {AppService} from 'RCO/Areas/ViewOrganization/AngularTemplates/app.service'

bootstrap(AppComponent, [HTTP_PROVIDERS, AppService]);

app.service.ts

import {Injectable} from 'angular2/core';
import {Http, Response} from 'angular2/http';
import {Observable} from 'rxjs/Rx';

@Injectable()
export class AppService {

    constructor(private http: Http) { }

    // Uses http.get() to load a single JSON file
    getTableData() {
        return this.http.get('...').map((res: Response) => res.json());
    }

}

我正在尝试调用服务器上的控制器,最终将JSON文件加载到数据表中.非常简单的东西,但我加载Http模块的方式似乎是错误的.任何帮助都感激不尽.

Answer 1

好像你没有使用typescript编译器来转换文件js,在这种情况下你需要@Inject在组件构造函数中注入任何依赖项时使用.

import {Injectable, Inject} from 'angular2/core';
import {Http, Response} from 'angular2/http';
import {Observable} from 'rxjs/Rx';

@Injectable()
export class AppService {
    constructor(@Inject(Http) private http: Http) { }
    // Uses http.get() to load a single JSON file
    getTableData() {
        return this.http.get('...').map((res: Response) => res.json());
    }
}

Answer 2

另一种方法是将来节省一些打字:

在你的tsconfig.json添加compilerOptions.emitDecoratorMetadata=true

简单的例子tsconfig.json是:

{
  "compilerOptions": {
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true
  }
}