Question

我有以下代码（基于Angular2 Hero示例），我试图将JSON API调用（AWS）转换为TypeScript类。

代码没有返回任何错误，我可以看到当我查看response.json（）时对象就在那里，但是类产品仍未定义，有什么想法吗？

服务文件中的代码......

  getProduct(id: number): Promise<Product> {
    const url = `${this.ProductsUrl}/${id}`;
    console.log(url);
    return this.http.get(url)
      .toPromise()
      .then(response => response.json().data as Product)
      .catch(this.handleError);
  }

组件文件中的代码......

  ngOnInit(): void {    
    this.route.params
      .switchMap((params: Params) => this.productsService.getProduct(+params['id']))
      .subscribe(product => this.product = product);
  }

班级......

export class Product {
  Instock: boolean;
  Description: string;
  CategoryId: number;
  Id: number;
  ColourOptions: string[];
  Name: string;
}

从API调用返回的JSON ...

{
"Instock":true,
"Description":"This is a test description.",
"CategoryId":1,"
Id":1,
"ColourOptions":["Red","Gold","Green"],
"Name":"Test"
}

Answer 1

case "FOO_BAR": const oldList = {...state.list}; const newKey1Value = action.payload.key.value; oldList.key1.value = oldList.key1.value.concat(newKey1Value); const newKey1fetching = action.payload.key.fetching; oldList.key1.fetching = newKey1fetching; return { ...state, list: oldList }＆＃39;回调必须返回switchMap而不是Observable，因此请修改Promise以返回getProduct：

Observable

通过http.get调用API并接收正确的JSON后，Angular2类未定义

1 个答案: