If/else statement combined with autocomplete search box using Ajax

I'm trying to implement an autocomplete search box that changes its autocomplete text based on the dropdown listitem selected in Javascript. However, I can't get this autocomplete to work when using if/else statements. I've posted my code below:

   <script type="text/javascript">  


            var DropdownList = document.getElementById("searchTypeDD");
            var SelectedValue = DropdownList.value;
            if (SelectedValue == "movieSearch") {

                data = "{'name':'" + document.getElementById('searchTermEntered').value + "'}",
                contentType = "application/json; charset=utf-8",
                url = "http://ift.tt/2mMKk7k",
                dataType = 'json';
            }

            else if (SelectedValue == "dirSearch") {
                data = "{'director':'" + document.getElementById('searchTermEntered').value + "'}",
                contentType = "application/json; charset=utf-8",
                url = "http://ift.tt/2n66m0C",
                dataType = 'json';
            }
            $(function () {
            $("[id$=searchTermEntered]").autocomplete({
                $:ajax({

                    type: "POST",

                    dataType: 'json',

                    data: data,

                    contentType: contentType,

                    url:url,

                    success: function (data) {

                        console.log(data);

                        response(data.d);

                    },

                    error: function (result) {

                        alert("No Match");

                    }

                })});

                }

)