角2号提供程序错误 [英] Angular 2 No provider error

问题描述

我创建简单的入门应用具有角2玩，我试图做一个待办事项服务并注入他到我的组成部分，我得到这个错误：

I am creating simple starter app to play with angular 2 and i am trying to make a todo service and inject him to my component and i get this error:

无提供商TodoService！ （TodoList的 - > TodoService）的

No provider for TodoService! (TodoList -> TodoService)

TodoService.ts

TodoService.ts

export class TodoService {
 todos: Array<Object>
 constructor() {
   this.todos = [];
 }
}

app.ts

app.ts

/// <reference path="typings/angular2/angular2.d.ts" />

import {Component, View, bootstrap, For, If} from 'angular2/angular2';
import {TodoService} from './TodoService'

@Component({
  selector: 'my-app'
})

@View({
  templateUrl: 'app.html',
  directives: [For, If],
  injectables: [TodoService]
})

class TodoList {
 todos: Array<Object>
  constructor(t: TodoService) {
    this.todos = t.todos
  }

  addTodo(todo) {
    this.todos.push({
      done:false,
      todo: todo.value
    });
  }
}

bootstrap(TodoList);

这是什么问题？

推荐答案

该注射剂是在指定的 @Component 不在 @View

The injectables are specified on the @Component not on the @View

您有：

@Component({
  selector: 'my-app'
})

@View({
  templateUrl: 'app.html',
  directives: [For, If],
  injectables: [TodoService]  // moving this line
})

将其更改为：

@Component({
  selector: 'my-app',
  injectables: [TodoService]  // to here
})

@View({
  templateUrl: 'app.html',
  directives: [For, If]
})

这将使DI把它捡起来，并注入到你的组件。

This will allow DI to pick it up and inject it into your component.

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