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如何阅读JSON数组,Android Java

[英]How Read JSON Array, Android Java

I need to read this JSON array : 我需要阅读以下JSON数组:

[{
"1":{"id":"0","name":"first"},
"2":{"id":"1","name":"second"}
}]

I use this code 我用这个代码

    JSONObject jsonObject = null;
    for(int i=0; i < array.length(); i++)
    {
        try 
        {
            jsonObject = array.getJSONObject(i);
            System.out.println("Data: " + jsonObject.getString("id"));
        }
        catch (JSONException e) 
        {
            Log.e("Get Data from JSON Array ..", "Error: " + e.getMessage());
        }
    }

But the array length = 1 always and the error appear : no value for id 但是数组长度始终为1,并且会出现错误:id无值

The method to return JSON Array .. 返回JSON Array的方法。

    public static JSONArray getJSONArrayFromUrl(String url)
{
    String str = "{\"Array\":["; // I add it because the JSON return from the site not contains root ..
    HttpResponse response;
    HttpClient myClient = new DefaultHttpClient();
    HttpPost myConnection = new HttpPost("url);        
    try 
    {
        response = myClient.execute(myConnection);
        str += EntityUtils.toString(response.getEntity(), "iso-8859-1") + "]}";
    }
    catch (ClientProtocolException e) {
        Log.e("Client Protocol Exception", "Error: " + e.getMessage());
    } 
    catch (IOException e) {
        Log.e("IO Exception", "Error: " + e.getMessage());
    }

    JSONObject obj = null;
    JSONArray array = null;

    try  {
        obj = new JSONObject(str);
        array = obj.getJSONArray("Array");
    } 
    catch (JSONException e) {
        Log.e("JSON Exception", "Error: " + e.getMessage());
    }

    return array;
}

How to solve it or how to read the JSON text .. 如何解决它或如何读取JSON文本..

Thanks ,, 谢谢 ,,

At first you need to create a class like this one: 首先,您需要创建一个像这样的类:

public class ExampleClass { 
    int id; 
    String name; 
}

And then you call it in your try: 然后您可以尝试调用它:

Gson gson = new Gson(); 
Type listOfTestObject = new TypeToken<ArrayList<ExampleClass>>() { }.getType(); 
ArrayList<ExampleClass> arrayInJSON = gson.fromJson(exampleJSONObject, listOfTestObject);

Then, you can use the response from JSON to get the size: 然后,您可以使用JSON的响应来获取大小:

arrayInJSON.size();

It is an array with one element on it [{ "1":{"id":"0","name":"first"}, "2":{"id":"1","name":"second"} }] 它是一个带有一个元素的数组[{“ 1”:{“ id”:“ 0”,“ name”:“ first”},“ 2”:{“ id”:“ 1”,“ name”: “第二”}}]

  becouse it look like [{...}] 

  here {...} is a map of 2 elements it is not array 
  jsonObject.getString("1").getString("id") in your code should return     what you need 

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