Question

When I try to convert an HTTP POST response to JSONArray I get the error:

org.json.JSONException: Value of type java.lang.String cannot be converted to JSONArray

the error happens in the line: JSONArray jArray = new JSONArray(result);

the value of the string result is [{“return”:”1″}] but it includes an extra blank character at the beginning that when removed, solves the problem. However, this character is not blank because a trim does not solve the problem. I believe there is some problem with the POST response, maybe badly constructed? (or maybe the POST request is wrong?) Any help is welcome.

A GET request works just fine, but I need to do a POST request.

This is the code:

HttpPost("usuarioLogin.php",nameValuePairs);
String result = ConvertResponseToString();
try{

    JSONArray jArray = new JSONArray(result);
    JSONObject json_data=null;
    for(int i=0;i<jArray.length();i++){
        json_data = jArray.getJSONObject(i);                
        ret = json_data.getInt("return");   
            retorno = (ret==1)?true:false;
    }               

}
catch(JSONException e1){          
      e1.printStackTrace();       
} catch (ParseException e1) {
    e1.printStackTrace();
}       

this is the code of the function HttpPost()

private void HttpPost(String php, ArrayList<NameValuePair> nameValuePairs)
{
            try{
                  HttpClient httpclient = new DefaultHttpClient();
                  String host = com.android.taggies.LoginUser.getContext().getResources().getString(R.string.host);
                  HttpPost httppost = new HttpPost("http://"+host+php);
                  httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

                  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());
            }
}

this is the code of the function ConvertResponseToString()

private String ConvertResponseToString()
{
    //convert response to string
    String result = null;
    try{
        //BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
        BufferedReader reader = new BufferedReader(new InputStreamReader(is,"utf-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());
    }

    return result;
}

this is the code of my php that replies to the POST

<?php
mysql_connect("localhost","root","");
mysql_select_db("dbTaggies");

$q=mysql_query("SELECT count(*) as 'return' FROM users
WHERE name='$_POST[user]' AND password ='$_POST[pass]'");

while($e=mysql_fetch_assoc($q))
{
        $output[]=$e;
}       

print(json_encode($output));

mysql_close();
?>

Answer 1

The problem is solved.

PHP files were saved in UTF-8 WITH BOM, the solution was saving the files in UTF8 no BOM and the initial character in the POST response was removed.