Convert AJAX call from jQuery 1.4 to 1.8

Convert AJAX call from jQuery 1.4 to 1.8

I have the following code that works well if I use jQuery 1.4 however I would like to upgrade to latest version 1.8 and this code returns '0 error' when jQuery above 1.5 is used.

Would someone know what i need to change to make it 1.8 compatible please.

  2. <html xmlns="http://www.w3.org/1999/xhtml">
  3. <head runat="server">
  4.     <title>PA Web Test</title>
  5.     <script src="jquery-1.8.0.js" type="text/javascript"></script>
  6.     <script type="text/javascript">
  7.         
  8.         var offset = 0;
  9.         var howMany = 5;
  10.         
  11.         $(document).ready(function() {
  12.             $("#btnMore").click(function() {
  13.                 // fetch some more records from the server side
  14.                 $.ajax({
  15.                     type: "POST",
  16. dataType: "json",
  17.                     contentType: "application/json; charset=utf-8",
  18.                     url: "http://localhost/PA_Web.asmx/GetData",
  19.                     data: "{'offset':" + offset + ",'howMany':" + howMany + "}",
  20.                     success: onSuccess,
  21.                     error: onError  
  22.                 });
  23.             });
  24.         });

  26.         function onSuccess(result) {
  27.             // process web service return data
  28.             // populate ul with data
  29.             $("#datalist").empty();
  30.             var strings = result.d;
  31.             for (var i = 0; i < strings.length; i++)
  32.                 $("#datalist").append("<li>" + strings[i] + "</li>");
  33.             // move offset
  34.             offset += howMany;
  35.         }

  37.         function onError(result) {
  38.             // ajax call failed
  39.             alert(result.status + ': ' + result.statusText);
  40.         }
  41.     </script>
  42. </head>
  43. <body>
  44.     <form id="form1" runat="server">
  45.     <div>
  46.         <ul id="datalist"></ul>
  47.         <br />
  48.         <input type="button" id="btnMore" value="more" />
  49.     </div>
  50.     </form>
  51. </body>
  52. </html>