While implementing AJAX call users find problem what to return and how to handle it.

The below example shows, web method which is returning a string in both the cases whether insertion occurs or error is being generated by the program.

 [WebMethod]
        [ScriptMethod]
        public static string InsertDetails(User user)
        {
            string status = null;
            try
            {
                UserRepository repobj = new UserRepository();
                user = repobj.GetPrefernceId(user);
                user = repobj.InsertData(user);
                status = "Records inserted successfully";
            }
            catch (Exception ex)
            {
                status = ex.Message;

            }
            return status;
        } 

To handle this, message i have made two methods in which on success and on error i will get string

Ex:
 function InsertDetails() {
            var user = {};
            user.Username = $("[id*=txtUserName]").val();
            user.Password = $("[id*=txtPassword]").val();
            user.Email = $("[id*=txtEmail]").val();
            user.Contact = $("[id*=txtContact]").val();
            user.Address = $("[id*=txtAddress]").val();
            user.Preference = $("[id*=txtPreference]").val();
            $.ajax({
                type: "POST",
                url: "RegisterUser.aspx/InsertDetails",
                data: '{user: ' + JSON.stringify(user) + '}',
                contentType: "application/json; charset=utf-8",
                dataType: "json",
                success: function (response) {
                    alert(response.d);
                    window.location.reload();
                },
                error: function (response) {
                    alert("Some error occurred","Error Description"+response.d);
                    window.location.reload();
                }
            });

            return false;
        }

So by defining these two methods i get the returning message and display message according to the return type.