POST http://localhost:62622/MyWork/ServiceGetTrainingDate.asmx/GetTrainingDates 500 (Internal Server Error)

HI All,

I have created a webservice (asmx). Service is running fine. But when I try to call this service using Jquery ajax, then it can not be find anywhere.

Below is my code to call service.

<script type="text/javascript">

                                        debugger;
                                            $.ajax({
                                            type: "POST",
                                            contentType: "application/json; charset=utf-8",
                                            url: "ServiceGetTrainingDate.asmx/GetTrainingDates",
                                            data: "{ user_id: '" + 1006 + "'}",
                                            datatype: "json",
                                            success: function (data) {
                                                alert(data.d);
                                            },
                                            error: function (XMLHttpRequest, textStatus, errorThrown) {
                                                debugger;
                                            }
                                        });</script>

Please help where I am making mistake?