Pass multiple Name Value pair JSON to WebMethod in ASP.Net

Hi,

This is regarding your article on 

http://www.aspsnippets.com/Articles/Send-and-Receive-JSON-objects-to-Web-Service-Methods-using-jQuery-AJAX-in-ASPNet.aspx#comments

I have a json object with multiple Name & Value pairs,  I am using example on above given link but it is not calling the Web Method.

var jd = [];

jd.push({ ID: HArr[j], Val: Str });

var jd = [];

for (var i = 0; i < jsonData.length / Tcnt; i++) {

var ctrl;

for (var j = 0; j < Tcnt; j++) {
                        ctrl = (parseInt(i) * parseInt(Tcnt)) + parseInt(j);
                        Str = jsonData[ctrl];
                        jd.push({ ID: HArr[j], Val: Str });    //Pushing values to Json Array               
                    }
                }


$.ajax({
                type: 'POST',
                url: 'PageName.aspx/PassJsonData',
                data: "{jd:" + JSON.stringify(jd) + "}",
                contentType: 'application/json; charset=utf-8',
                dataType: "json",
                success: function(r) {
                    alert(r.d.ID);
                    alert(r.d.Val);
                },
                failure: function(response) {
                    alert(response.d);
                }
            });

In code behind I have created a class with two attributes ID and Val.

 public class jsonData

    {
        private string id;
        public string ID{get{return id;}set{id = value;}}

        private string val;
        public string Val { get { return val; } set { val = value; } }

    }

In my class I have a Web Method defined as :

 [System.Web.Services.WebMethod]

        public static jsonData PassJsonData(jsonData jd)
        {
            return jd;
        }