java - 如何解析数组中的 JSON 字符串

Question

我有以下格式的 json:

{    "Result": {        "question": "Barack Obama vs Mitt Romney?",        "option": [            "Barack Obama",            "Mitt Romney",            "Other"                   ],        "percentage": [            20,            40,            80                      ]               }}

and I am using following code to parse it but this giving null pointer exception at option array.

JSONParser jParser = new JSONParser();

                    JSONObject json = jParser.getJSONObjectFromUrl(url);
                    Log.e("json",json.toString());

                    Log.e("-------url-------", ""+url);


                        String resultStr = json.getString("Result"); 
                        Log.e("result string ",resultStr);

                        JSONObject jsonObject2 = new JSONObject(resultStr);


                        String question_string = jsonObject2.getString("question"); 
                        Log.e("question String ",question_string);


                        String option_str = jsonObject2.getString("option"); 

                        JSONArray optionArray = new JSONArray(option_str);
                        Log.d("option array", String.valueOf(optionArray.length()));

Answer 1

你需要这样获取json数组:

JSONArray optionArray = jsonObject2.getJSONArray("option");
Log.d("option array", String.valueOf(optionArray.length()));

检查http://www.androidhive.info/2012/01/android-json-parsing-tutorial/