php - 如何从服务器获取计数值到android中的json？

Question

我正在尝试在 android 中使用 json 解析和 php 检索我的服务器表中的行数。我在 php 中完成了以下编码，我也得到了值，但我不知道如何处理 json。请逐步指导我该做什么或我哪里出错了。我的代码和错误日志如下:

php代码:

<?php
mysql_connect("localhost","user","pswd");
mysql_select_db("demo");    
$username= (isset($_POST['receivenumber'])) ? $_POST['receivenumber'] : '';
$q=mysql_query("SELECT COUNT(receivenumber) FROM `addtasknew` where `receivenumber` = '$username'") or die(mysql_error());
$row=mysql_fetch_assoc($q);
print (json_encode($row));
mysql_close();
?>

android中的json代码

   String result = null;
    InputStream is = null;
    try{
            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httppost = new HttpPost("http://www.mydomainname.org/task/getmytaskcount.php");
            ArrayList<NameValuePair>  nameValuePairs = new ArrayList<NameValuePair>();
           // String h="123";
            //nameValuePairs.add(new BasicNameValuePair("to",h.toString()));
            nameValuePairs.add(new BasicNameValuePair("receivenumber","9595959595"));

             httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
            HttpResponse response = httpclient.execute(httppost); 

            HttpEntity entity = response.getEntity();
            is = entity.getContent();

            Log.e("log_tag", "connection success "+nameValuePairs);

    }
    catch(Exception e)
    {
            Log.e("log_tag", "Error in http connection "+e.toString());
            Toast.makeText(getActivity(), "Connection fail", Toast.LENGTH_SHORT).show();

    }
    try
    {
            BufferedReader reader = new BufferedReader(new InputStreamReader(is,HTTP.UTF_8),8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) 
            {
                    sb.append(line + "\n");

            }
            is.close();

            result=sb.toString();
          Log.e("log_tag", "result "+result.toString());
    }
    catch(Exception e)
    {
           Log.e("log_tag", "Error converting result "+e.toString());
        Toast.makeText(getActivity(), " Input reading fail", Toast.LENGTH_SHORT).show();

    }
    try
    {

                 // I don't know wht to do here to get the count value
        JSONArray jArray = new JSONArray(result);

          Log.w("Lengh",""+jArray);
             }
    catch(JSONException e)
    {
            Log.e("log_tag", "Error parsing data "+e.toString());
            Toast.makeText(getActivity(), "JsonArray fail", Toast.LENGTH_SHORT).show();
    }

错误日志:

  E/log_tag(2386): result ?{"COUNT(receivenumber)":"2"}
  E/log_tag(2386): Error parsing data org.json.JSONException: Value {"COUNT(receivenumber)":"2"} of type org.json.JSONObject cannot be converted to JSONArray

Answer 1

您正试图将您的 JSON 解释为 JSONArray，但它是一个 JSONObject。

要检索您的值，试试这个:

JSONObject jObj = new JSONObject(result);
String count= jObj.getString("COUNT(receivenumber)");

你可以查看这个tutorial了解有关 Android 中的 JSON 的更多信息。