Database table filtered autocomplete input data according to selected field

I want to show filtered data as an autocomplete input according the selected by userId in an input field. I have userId, data fields in database table. In the page, when user enters a data to an input field I want to show only this user’s data fields as an autocomplete field. How can I do this. I hope I clarified the problem.

The following code works without filtering:

 <%@ Control Language="C#" AutoEventWireup="true" 
CodeFile="AutoCompleteParameterTextBox.ascx.cs"       Inherits="AutoCompleteParameterTextBox" %> 
<script type="text/javascript">
jQuery(function ($) {
    try {
        if ($('script[src="/Assets/js/jquery-ui-1.10.4.custom.min.js"]').length == 0) {
            var s = document.createElement("script");
            s.type = "text/javascript";
            s.src = "/Assets/js/jquery-ui-1.10.4.custom.min.js";
            $("body").append(s);
        }
        if ($('link[href="/Assets/css/jquery-ui.min.css"]').length == 0) {
            $("head").append('<link rel="stylesheet" href="/Assets/css/jquery-ui.min.css" 
 type="text/css" />');
        }
    }
    catch (err) {
    }
});

function CallServer() {
    <%=PostBackScript%>
}

function stripNonAlphaNumeric(string) {
    var r = string.toLowerCase();
    r = r.replace(new RegExp("[^A-z0-9şŞıİçÇöÖüÜĞğ.,-/() ]", 'g'), "");
    return r;
}

var initAutoComplete
    = (function () {
        $(function () {
            $("#<%=txt.ClientID%>").autocomplete({
                source: function (request, response) {
                    var hiddenInputValueName = $("#<%=hdnRadioId.ClientID %>").val();
                    if (hiddenInputValueName) {
                        var inputValue = $('input[name$="' + hiddenInputValueName + 
     '"]:checked').val();
                        if (inputValue) request.term = inputValue + '-' + request.term;
                        else {
                            $("#<%=txt.ClientID%>").val('');
                            return false;
                        }
                    }

                    var host = "";

                    if (window.location.hostname == "localhost") {
                        host = '<%=GetBaseUrl()%>';
                    }
                    else {
                        host = window.location.protocol + "//" + window.location.host;
                    }
                    var parametertable = '<%=ParameterTable%>';

                    if ((hiddenInputValueName && request.term.substr(2).trim() === '') || 
    (!hiddenInputValueName && request.term.trim() === '')) response(null);
                    else {
                        $.ajax({
                            url: host + "/api/parameterapi/" + parametertable + "/" +

    stripNonAlphaNumeric(request.term),
                            dataType: "json",
                            success: function (data) {
                                response($.map(data, function (item) {
                                    return {
                                        label: item.Aciklama,
                                        value: item.KayitNo
                                    }
                                }));
                            }
                        });
                    }
                },
                autoFill: true,
                minLength: 3,
                delay: 300,
                select: function (event, ui) {
                    $("#<%=txt.ClientID %>").val(ui.item.label);
                    $("#<%=hdn.ClientID %>").val(ui.item.value.toString());
                    CallServer();
                    return false;
                },
                focus: function (event, ui) {
                    $("#<%=txt.ClientID %>").val(ui.item.label);
                    return false;
                },
                change: function (event, ui) {
                    $("#<%=hdn.ClientID %>").val(ui.item ? ui.item.value : "");
                },
                open: function () {
                    $(this).removeClass("ui-corner-all").addClass("ui-corner-top");
                },
                close: function () {
                    $(this).removeClass("ui-corner-top").addClass("ui-corner-all");
                },
                error: function (response) {
                    alert(response.responseText);
                },
                failure: function (response) {
                    alert(response.responseText);
                }
            }).blur(function () {
                //$(this).autocomplete("close");
            }).data("ui-autocomplete")._renderItem = function (ul, item) {
                var newText = String(item.label).replace(
                    new RegExp(this.term, "gi"),
                    "<span class='ui-state-highlight'>$&</span>");

                return $("<li></li>")
                    .data("item.autocomplete", item)
                    .append("<a>" + newText + "</a>")
                    .appendTo(ul);
            };
        });
    });

    if (undefined === window.Sys) {
        initAutoComplete();
    }
    else {
          Sys.Application.add_load(function (s, e) {
            initAutoComplete();
        });
       }
  </script>
  <asp:TextBox runat="server" ID="txt" CssClass="input-xlarge"></asp:TextBox>
  <asp:Label runat="server" ID="lblRequired" CssClass="REQUIRED" Text="*" Visible="false" />
  <asp:HiddenField runat="server" ID="hdn" />
  <asp:HiddenField runat="server" ID="hdnParameterTable" />
  <asp:HiddenField runat="server" ID="hdnRadioId" />
  <span><small>
    <asp:Label runat="server" ID="lbl">Üç Harf Giriniz.</asp:Label></small></span>