Question

每个news条目都有三个内容：title，content和date。

从数据库中检索条目，我想在我的应用程序中使用JSONObject和JSONArray读取它们。但是，我不知道如何使用这些类。

这是我的JSON字符串：

[
   {
      "news":{
         "title":"5th title",
         "content":"5th content",
         "date":"1363197493"
      }
   },
   {
      "news":{
         "title":"4th title",
         "content":"4th content",
         "date":"1363197454"
      }
   },
   {
      "news":{
         "title":"3rd title",
         "content":"3rd content",
         "date":"1363197443"
      }
   },
   {
      "news":{
         "title":"2nd title",
         "content":"2nd content",
         "date":"1363197409"
      }
   },
   {
      "news":{
         "title":"1st title",
         "content":"1st content",
         "date":"1363197399"
      }
   }
]

Answer 1

您的JSON字符串是JSONArray JSONObject，其中包含一个名为“news”的内部JSONObject。

尝试使用它来解析它：

JSONArray array = new JSONArray(jsonString);

for(int i = 0; i < array.length(); i++) {
    JSONObject obj = array.getJSONObject(i);
    JSONObject innerObject = obj.getJSONObject("news");

    String title = innerObject.getString("title");
    String content = innerObject.getString("content");
    String date = innerObject.getString("date");

    /* Use your title, content, and date variables here */
}

Answer 2

首先，您的JSON结构并不理想。你有一个对象数组，每个对象都有一个对象。但是，您可以这样阅读：

JSONArray jsonArray = new JSONArray (jsonString);
int arrayLength = jsonArray.length ();

for (int counter = 0; counter < arrayLength; counter ++) {
    JSONObject thisJson = jsonArray.getJSONObject (counter);

    // we finally get to the proper object
    thisJson = thisJson.getJSONObject ("news");

    String title = thisJson.getString ("title");
    String content = thisJson.getString ("content");
    String date = thisJson.getString ("date");

}

<强>然而！

如果将JSON更改为如下所示，则可以做得更好：

[
    {
        "title": "5th title",
        "content": "5th content",
        "date": "1363197493"
    },
    {
        "title": "4th title",
        "content": "4th content",
        "date": "1363197454"
    }
]

然后，您可以按如下方式解析它：

JSONArray jsonArray = new JSONArray (jsonString);
int arrayLength = jsonArray.length ();

for (int counter = 0; counter < arrayLength; counter ++) {
        // we don't need to look for a named object any more
    JSONObject thisJson = jsonArray.getJSONObject (counter);    

    String title = thisJson.getString ("title");
    String content = thisJson.getString ("content");
    String date = thisJson.getString ("date");
}

在Java中读取JSON二维数组

2 个答案: