Pass user defined object to ASP.NET Webmethod from jQuery, using JSON

In .html page

  <script>

        function StoreDataInDatabse() {

            debugger;

            var Employee_Detail = {}

            Employee_Detail.Emp_Name = "Test";

            Employee_Detail.Emp_Age = "24";

            Employee_Detail.Emp_Salary = "1000";

            Employee_Detail.Emp_City = "Ban";

            $.ajax({

                type: "POST",

                url: "default.aspx/Insert_Data",

                dataType: "json",

                contentType: "application/json; charset=utf-8",

            data: JSON.stringify({ 'Employee_Detail': Employee_Detail }), // Check this call.

                success: function () {

                    alert("Data Has Inserted")

                }

            })

        }

    </script>

<div>

 <input type="button" id="btnSave" value="Save Data" onclick="StoreDataInDatabse()"/>

               

</div>

Default.aspx.cs file

[WebMethod]

        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]

        public static void Insert_Data(Employee_Detail Employee_Detail)

        {

        }

Class file

public class Employee_Detail

    {

        public string Emp_Name { get; set; }

        public string Emp_Age { get; set; }

        public string Emp_Salary { get; set; }

        public string Emp_City { get; set; }

    }

use same properties names in both places(client side and server side)