如何訂閱自定義模型Angular 2？

Question

我有以下自定義模式：

export class CreateEducationYear { 

    public year: number; 
    public name: string; 

} 

我用這部分是這樣的：

public newEducationYearModel: Observable<CreateEducationYear>; 
constructor() { 
    this.newEducationYearModel = new Observable<CreateEducationYear>(); 
} 

// Subscribe method 

public test(): Observable<CreateEducationYear> { 
    return this.newEducationYearModel; 
} 

// Listening 

ngOnInit() { 
    this.test().subscribe(data => { 
     console.log(data); 
    }); 
    } 

我得到一個錯誤：

TypeError: Cannot read property 'subscribe' of undefined

我該怎麼辦錯了嗎？

模板是：

{{newEducationYearModel | json }} 
<div class="filter-search-item-sub col-md-3"> 
    <label>Название периода</label> 
    <input [(ngModel)]="newEducationYearModel.name" name="period" type="text" value=""/> 
</div> 

後首次發射我控制檯中看到CreateEducationYear {year: 2000}。但進一步，當我改變模型沒有什麼變化。

Answer 1

更改您的代碼

public newEducationYearModel: CreateEducationYear; 
constructor() { 
    this.newEducationYearModel = new CreateEducationYear(); 
} 

// Subscribe method 

public test(): Observable<CreateEducationYear> { 
    return Observable.of(this.newEducationYearModel); 
} 

並添加

import "rxjs/add/observable/of"; 

編輯：這裏是一個plunker https://plnkr.co/edit/KSOSvhe4C1uhTcLc7XML

Answer 2

變化test方法是這樣的：

public test(): Observable<CreateEducationYear> { 
    return Observable.of(this.newEducationYearModel); 
}