Question

我有一个名为fetchProperties的操作，用于获取所有列表和与数据相关的所有数据。响应看起来像这样，我正在为Redux存储设置此信息（20个列表）。

{
  "status":"success",
  "listings":[
             {
               "id": "1",
               "streetnum": "370",
               "streetname": "Pack Saddle Drive",
               "city": "Horseshoe Bay",
               "area": "Blue Lake Estates",
               "zipcode": "78657",
             },
             {...}
             // 20 out of 300 properties
             ],
  "total_found":300,
  "some_other" : "some other data"
}

在下一次调用中提取接下来的20个列表时，API返回与上述相同的结构，但是我想将新的listings数组追加到Redux存储中的旧listings数组。 / p>

对于这种情况，如何编写减速器？我尝试如下所示，但没有成功，

    export default function propertiesList(state = { listings: [] }, action) {
  switch (action.type) {
    case FETCH_PROPERTIES:
      // return action.payload.body;
      return {
        ...state,
        listings: [...state.listings, ...action.payload.body]
      };
}

，最终状态应为：

{
  "status":"success",
  "listings":[
             {
               "id": "1",
               "streetnum": "370",
               "streetname": "Pack Saddle Drive",
               "city": "Horseshoe Bay",
               "area": "Blue Lake Estates",
               "zipcode": "78657",
             },
             {...}
             // 40 out of 300 properties
             ],
  "total_found":300,
  "some_other" : "some other data"
}

Answer 1

在reducer成功的情况下，您只需要在清单上附加旧清单即可，例如：

case FETCH_PROPERTIES:
  return { 
    ...state, 
    listings: [
      ...state.listings,
      ...action.payload.body,
    ]
  }

假设FETCH_PROPERTIES是您的成功案例

Answer 2

我已将减速器更改为这样。

public DownloadStringResult DownloadString(string url)
{
    DownloadStringResult result = new DownloadStringResult();
    try
    {
        var html = base.GetStringAsync(url).Result; // base is HttpClient.
        if (html.Contains(WebSiteDto.LogoutMessage) || html.Contains("Please Login")) // Log-out website. So I need to re-login again.
        {
            result.IsRelogged = true;
            result.HtmlResult = GetLoginResult(); // re-login
            return result;
        }
        result.HtmlResult = html;
    }
    catch (Exception e) // This try catch for TimeOut Exception. I try many way but I still cant catch timeout exception. Or I cant tell wait just 5 second, if no answer then retry again.
    {
        return DownloadString(url);
    }

    return result;
}

并且在第一次调用export default function propertiesList(state = { listings: [] }, action) { switch (action.type) { case FETCH_PROPERTIES: return { ...action.payload.body, listings: [...state.listings, ...action.payload.body.listings] }; case EMPTY_PROPERTIES_STORE: return { listings: [] }; }之前，我调用了操作fetchProperties，以确保我的空存储中包含空的EMPTY_PROPERTIES_STORE数组

如何在React Native Redux-Reducer

2 个答案: