Javascript Ping by Downloading JSON file

I'm trying to download a JSON file through javascript to use in a ping test but the browser appears to be interpreting it as javascript and gives parse errors. here is the code:

function sprawdz(adres)
    {
     //ping = 0;                            
     startTime = new Date().getTime( );

     $.ajax({
       type: 'GET',
       //url: 'http://'+adres+'/img/loading.gif',
       url: 'URL TO JSON FILE HERE',
       dataType: 'jsonp',
       async: false,
       setup: function() {
        //
       },
       complete: function(xhr, text)
       {
  开发者_如何转开发      //alert(xhr.status + ' - ' + xhr.responseText + ' - ' + xhr.status);
        finishTime = new Date( ).getTime( );   
        ping = finishTime - startTime;
        //pngud(ping);
       }
      }
     );
     //return ping + ' ms';
    }

You are specifying a dataType of JSONP. JSONP is JavaScript.

Did you mean dataType: 'json'?

Let's try to get a better idea of what the server is actually sending to you. Try this:

$.ajax({
    type: 'GET',
    url: '/json/ping',
    dataType: 'text',
    async: false,
    success: function(data) {
        console.log(data);
    }
});

What shows up in the console?

its interpreted as json and should be a valid json string then. however what on earth is your definition of "ping"?