AutoComplete can't working. Would someone help?

Hi All,

I have search some documents from web and try to develope the autocomplete by myself. However, it can't work and I really can't find out what the problem is. Would someone give me some advice?

1. I have created a App_Code folder under my project manually

2. Created a AutoComplete.asmx under the App_Code folder

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;

namespace SHS.App_Code
{
    /// <summary>
    /// Summary description for AutoComplete
    /// </summary>
    [WebService(Namespace = "http://tempuri.org/")]
    [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    [System.ComponentModel.ToolboxItem(false)]
    [System.Web.Script.Services.ScriptService]
    // To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line. 
    // [System.Web.Script.Services.ScriptService]
    public class AutoComplete : System.Web.Services.WebService
    {
        public AutoComplete()
        {
        }

        [System.Web.Services.WebMethod]
        [System.Web.Script.Services.ScriptMethod]
        public string[] GetCompletion(string prefixText, int count)
        {

            if (count == 0)
            {
                count = 10;
            }

            List<string> tmp = new List<string>(count);
            Random rnd = new Random();

            for (int i = 1; i < count; i++)
                tmp.Add(prefixText + rnd.Next(10).ToString() + rnd.Next(10).ToString() + rnd.Next(10).ToString());

            return tmp.ToArray();


        }
    }
}

3. Create test2.aspx

<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="test2.aspx.cs" Inherits="SHS.Views.temp.test2" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="ajax" %>
<asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
</asp:Content>
<asp:Content ID="Content3" ContentPlaceHolderID="MainContent" runat="server">
<ajax:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server">
    <Services>
        <asp:ServiceReference Path = "~/App_Code/AutoComplete.asmx"/>
    </Services>
</ajax:ToolkitScriptManager>

<div>
    <asp:Label ID="ErrMsg" runat="server" Text="Label"></asp:Label>

    <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
    <ajax:AutoCompleteExtender ID="AutoCompleteExtender1" 
        runat="server" 
        TargetControlID="TextBox1" 
        ServiceMethod="GetCompletion"
        ServicePath="~/App_Code/AutoComplete.asmx"
        MinimumPrefixLength="2"
        CompletionInterval = "1"
        CompletionSetCount="10"
        EnableCaching="true">
    </ajax:AutoCompleteExtender>    

</div>

</asp:Content>