我实现了一个返回 JSON 字符串的 Web 服务,如下所示:
{"checkrecord":[{"rollno":"abc2","percentage":40,"attended":12,"missed":34}],"Table1":[]}
在我的 Android 应用程序中,我试图将字符串解析为 JSONArray,但我无法这样做,因为我在 logcat 中遇到以下异常:
11-16 22:15:57.381: ERROR/log_tag(462): Error parsing data org.json.JSONException: Value <?xml of type java.lang.String cannot be converted to JSONArray
如何解决这个问题?
我的安卓代码如下:
public static JSONArray getJSONfromURL(String b)
{
//initialize
InputStream is = null;
String result = "";
JSONArray jArray = null;
//http post
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Log.e("log_tag", "Error in http connection "+e.toString());
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
}catch(Exception e)
{
Log.e("log_tag", "Error converting result "+e.toString());
}
//try parse the string to a JSON array
try{
jArray = new JSONArray(result);
}
catch(JSONException e)
{
Log.e("log_tag", "Error parsing data "+e.toString());
}
return jArray;
}
这是返回json的web服务代码
public class Service1 : System.Web.Services.WebService
{
[WebMethod]
public String getdata(String rollno)
{
String json;
try
{
using (SqlConnection myConnection = new SqlConnection(@"Data Source=\SQLEXPRESS;Initial Catalog=student;User ID=sa;Password=123"))
{
string select = "select * from checkrecord where rollno=\'" + rollno + "\'";
SqlDataAdapter da = new SqlDataAdapter(select, myConnection);
DataSet ds = new DataSet();
da.Fill(ds, "checkrecord");
DataTable dt = new DataTable();
ds.Tables.Add(dt);
json = Newtonsoft.Json.JsonConvert.SerializeObject(ds);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
return null;
}
return json;
}
最佳答案
您的结果最初不是 JSONArray
,而是 JSONObject
。
试试这个:
JSONObject jsonResult = new JSONObject(new String(reader));
JSONArray jArray = jsonResponse.getJSONArray("checkrecord");
关于android - 解析从 .NET Web 服务返回的 JSONArray 时出错,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/8155510/