Angular 7 PATCH方法将元素添加到列表

时间:2019-02-14 07:06:21

标签: angular typescript rest api

我应该如何编写PATCH方法,使我可以在数组内部添加和删除数组的项目?

ItemClass:

export class ItemClass {
constructor(public person: string, public name: string, public quantity: number, public price: number){}
}

MenuModel:

    import { ItemClass } from './item.model';

    export class MenuModel {


    id: number;
    name: string;
    items: ItemClass[];

    constructor( id: number,  name: string, items: ItemClass[]){

         this.id = id;
         this.name = name;
         this.items = items;
    }
}

我有一个菜单组件和一个菜单服务。我需要一个修补方法,该方法可以将元素添加到Menu内的ItemClass []数组中,并且也可以将其删除。

API方法如下:

   @PATCH
   @Path("/add/{menuId}")
   public void removeMenuItem(
            @PathParam("menuId") final int menuId,
            final Item item) {  // Item represents the Request Body
      final List<Item> items = this.menuRepository.get(menuId).getItems();
      items.add(item);
   }

(来自https://stackoverflow.com/a/54679303/479251

1 个答案:

答案 0 :(得分:1)

在有关后端的补丁方法的其他详细信息之后,这是一个如何做的粗略示例。

您尚未为Angular指定版本,所以我想您使用的是最新版本(7)和HttpClient

import { HttpClient } from '@angular/common/http'; 
/* ... */ 
export class YourComponentOrService {

  // note : you will need to add HttpClientModule to the application module 'imports' and 'providers' sections
  constructor(private http: HttpClient) {} 

  /* ...*/ 

  // call this method when you want to add an item
  public addItem(menuID: number, itemToAdd: ItemClass): void { 
    console.log('sending patch request to add an item');

    this.http.patch(`example.com/add/{menuId}`, itemToAdd).subscribe(
      res => { 
        console.log('received ok response from patch request');
      },
      error => {
        console.error('There was an error during the request');
        console.log(error);
      });

    console.log('request sent. Waiting for response...');

  }

  // as I could see on the linked Q&A, the delete method will be very similar
  // only the url will use 'remove' instead of 'add', along with the item name, and no body.

  /* .... */
}     

当然,这是入门的基本“概念证明”,可以适应您的需求和Angular应用程序的总体架构。

如您所见,我所做的只是读取API端点,并相应地使用了patch Angular服务中的HttpClient方法,并带有预期的URL和内容。

现在,您必须添加逻辑以使用正确的参数发送请求。