没有键解析Json数组

Question

我想从服务器解析一个数组，但无法获取该数组。这是jsonString成功获取：

{
    "status":"OK",
    "message":"this is your start and end coordinates",
    "data":"{\"start\":[\"35.778763\",\"51.427360\"],\"end\":[\"35.768779, 51.415002\"]}"
}

我想要数据数组列表中的双值：

//try/catch
Log.d(TAG, "Passes here");          
JSONObject jObject = new JSONObject(jsonString);

JSONArray jData = jObject.getJSONArray("data");
Log.d(TAG, "Not PAASING HERE !!! ");

JSONArray jArrayStart = (JSONArray) jData.get(0);
JSONArray jArrayEnd =  (JSONArray) jData.get(1);

latitudeStart =  (Double) jArrayStart.get(0);
longtitudeStart = (Double) jArrayEnd.get(1);
latitudeEnd = (Double) jArrayEnd.get(0);
longtitudeEnd = (Double) jArrayEnd.get(1);

Answer 1

您要解析的是一个string 。

{
    "status": "OK",
    "message": "this is your start and end coordinates",
    "data": "{\"start\":[\"35.778763\",\"51.427360\"],\"end\":[\"35.768779, 51.415002\"]}"
}

所以它是这样的：

//first, retrieve the data from the response JSON Object from the server
JSONObject response = new JSONObject(jsonString);
String status = response.getString("status");
String message = response.getString("message");
//Note this: "data" is a string as well, but we'll have to parse that later.
String data = response.getString("data");

//get the doubles from the arrays from the "data" component.
JSONObject dataObject = new JSONObject(data);
JSONArray start = dataObject.getJSONArray("start");
JSONArray end = dataObject.getJSONArray("end");

for (int i = 0; i < start.length(); i++) {
    String value = start.getString(i);
    //do something with the start String (parse to double first)
}
for (int i = 0; i < end.length(); i++) {
    String value = end.getString(i);
    //do something with end String (parse to double first)
}

因此，数据实际上是一个String ，但是代表一个JSONObject （您必须对其进行解析），而JSONObject则包含两个JSONArrays 。

如果data是JSONObject而不是String ，那么JSON看起来应该像这样：

{
    "status": "OK",
    "message": "this is your start and end coordinates",
    "data": {
        "start": [
            "35.778763",
            "51.427360"
        ],
        "end": [
            "35.768779", //note that in your example, this quote is missing (first quote on next line too)
            "51.415002"
        ]
    }
}

Answer 2

data的值不是其JSONObject的JSONArray

说明

JSONObject将被{}包围

JSONArray将被[]包围

Answer 3

数据不是数组，它是json对象，因此您无法按自己的方式访问它。 如果要从json对象“ data”获取起始数组，请在下面使用jObject.optJSONObject（“ data”）。optJSONArray（“ start”）;

相同的东西可用于检索“ end” json数组。

然后使用optJSONObject（）和/或optString（）API从json数组中检索所需的值。