Question

当我JSONObject jsonObj = new JSONObject(jsonStr);时我输入catch因为我的json不是数组。我怎样才能获得这种格式？

     protected Void doInBackground(Void... arg0) {
            HttpHandler sh = new HttpHandler();
            // Making a request to url and getting response
            String url = "http://10.0.2.2:8080/PFA/crimes";
            String jsonStr = sh.makeServiceCall(url);

            Log.e(TAG, "Response from url: " + jsonStr);
            if (jsonStr != null) {
            try {
                JSONObject jsonObj = new JSONObject(jsonStr);

                // Getting JSON Array node
                JSONArray data = jsonObj.getJSONArray("crime");

                // looping through All Contacts
                for (int i = 0; i < data.length(); i++) {
                    JSONObject c = data.getJSONObject(i);
                    String day_week = c.getString("day_week");
                    String naturecode = c.getString("naturecode");


                    // tmp hash map for single contact
                    HashMap<String, String> contact = new HashMap<>();

                    // adding each child node to HashMap key => value
                    contact.put("day_week", day_week);
                    contact.put("naturecode", naturecode);

                    // adding contact to contact list
                    List.add(contact);
                }
            } catch (final JSONException e) {
                Log.e(TAG, "Json parsing error: " + e.getMessage());
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        Toast.makeText(getApplicationContext(),
                                "Json parsing error: " + e.getMessage(),
                                Toast.LENGTH_LONG).show();
                    }
                });

        }

    } else {
        Log.e(TAG, "Couldn't get json from server.");
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                Toast.makeText(getApplicationContext(),
                        "Couldn't get json from server. Check LogCat for possible errors!",
                        Toast.LENGTH_LONG).show();
            }
        });
    }

    return null;
}

JSON：

{
  "crime": {
    "compnos": "zerezrerzerezzr",
    "day_week": "rtkeertoeirtj ,ertkierj",
    "domestic": "false",
    "fromdate": "ekrjtner",
    "id": "1",
    "location": "etritkjrtoijty",
    "main_crimecode": "oijereriotjeroi",
    "month": "455",
    "naturecode": "zetzeeztet",
    "reportingarea": "58",
    "reptdistrict": "zorigjrgoijtoi",
    "shift": "rektenrloj",
    "shooting": "true",
    "streetname": "kjrtnerkj",
    "ucrpart": "irtjeroitejroirj",
    "weapontype": "kejfnergkrtnh",
    "x": "11",
    "xstreetname": "zekjrnetk",
    "y": "11",
    "year": "45"
  }
}

Answer 1

试试这个：

JSONObject jsonObj = new JSONObject(jsonStr);
JSONObject jsonMetaObject = jsonMasterObject.getJSONObject("crime");

而不是

 JSONObject jsonObj = new JSONObject(jsonStr);

            // Getting JSON Array node
  JSONArray data = jsonObj.getJSONArray("crime");

因为你在犯罪的关键中得到jsonObject而不是JsonArray。

Answer 2

JsonObject crime = jsonObj.getJsonObject（＆＃34; crime＆＃34;）;

JsonObject compnos = crime.getJsonObject（＆＃34; compnos＆＃34;）;

。 .. ...

你的json值中没有jsonArray。放弃获取jsonArray。

获取值json不在数组中

2 个答案: