Question

我的Android应用程序抛出JSONException，但我无法弄清楚原因！我正在使用一个php页面从MYSQL数据库中选择一些列并将它们放入这样的数组中：

$sql = "SELECT name,type,price FROM $tbname";
$result = $conn->query($sql);
$jsonarray=array();
if ($result->num_rows > 0) {
    // output data of each row
    while($row = $result->fetch_assoc()) {
$jsonarray[]=$row;
    }
$myJSON = json_encode($jsonarray);
echo $myJSON;

导致像这样的JSON：

[{"name":"sandwich","type":"food","price":"5000"},{"name":"pizza","type":"food","price":"10000"}]

但是当我尝试在Android Studio中解析上面的JSON时，它会抛出JSONException。我的java代码：我在类中有一个名为httpmanager的发送数据方法，如下所示：

public static String SendData(DataPack pack) throws IOException {
        URL url=new URL(pack.getUri());
        BufferedReader reader=null;
        HttpURLConnection connection= (HttpURLConnection) url.openConnection();
        connection.setDoOutput(true);
        OutputStreamWriter w=new OutputStreamWriter(connection.getOutputStream());
        w.write(pack.Encode());
        w.flush();
        StringBuilder sb=new StringBuilder();
        reader=new BufferedReader(new InputStreamReader(connection.getInputStream()));
        String line;
        while((line=reader.readLine())!=null){
            sb.append(line + "\n");
        }
        return sb.toString();
    }

然后我有一个带有onpostexecute方法的Asynctask类，如下所示：

protected void onPostExecute(String s) {
    String jsonStr = s;
    if (jsonStr != null) {
        try {
            JSONObject jsonObj = new JSONObject(jsonStr);
            Toast.makeText(context, "JSON recieved!", Toast.LENGTH_SHORT).show();
            }
        } catch (JSONException e) {
            e.printStackTrace();
            Toast.makeText(context, "Error parsing JSON data.", Toast.LENGTH_SHORT).show();
        }
    } else {
        Toast.makeText(context, "Couldn't get any JSON data.", Toast.LENGTH_SHORT).show();
    }
}

我很感激有关此事的任何帮助

Answer 1

如何解析de JSON？

您需要使用try/catch方法！

我使用这样的东西：

 HttpURLConnection connection = null;
        BufferedReader reader = null;

        try {

            URL url = new URL(params[0]);
                connection = (HttpURLConnection) url.openConnection();
                connection.connect();
            InputStream stream = connection.getInputStream();
            reader = new BufferedReader(new InputStreamReader(stream));

            StringBuffer buffer = new StringBuffer();
                String line = "";
                    while ((line = reader.readLine()) != null) {
                        buffer.append(line);
                    }

            String finalJson = buffer.toString();

           //Code for getting objects/arrays


     }catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (JSONException e) {
            e.printStackTrace();
        } finally {
            if (connection != null) {
                connection.disconnect();
            }
            try {
                if (reader != null) {
                    reader.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }

        }

获得JSONException的Android应用

1 个答案: