Autocomplete extender not firing

Question

Hello. I have a ajax autocomplete extender and everything works fine. I mean sql procedure and others are fine but when I enter something to textbox nothing happened. Why is that?

Here is my codes.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Configuration;
using System.Data;
using System.Data.Sql;
using System.Data.SqlClient;

/// <summary>
/// Summary description for WebService
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
// 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 WebService : System.Web.Services.WebService {

    string[] arr;

    public WebService () {

        //Uncomment the following line if using designed components 
        //InitializeComponent(); 
    }

    [WebMethod]
    public string[] testing(string prefixText)
    {
        if (prefixText.Length > 0)
        {
            string sql = "Select * From titles Where title like @title";

            SqlDataAdapter da = new SqlDataAdapter(sql, "myconnectionstring is here");
            da.SelectCommand.Parameters.Add("@title", SqlDbType.VarChar, 50).Value = prefixText + "%";
            DataTable dt = new DataTable();
            da.Fill(dt);

            string[] items = new string[dt.Rows.Count];

            int i = 0;

            foreach (DataRow dr in dt.Rows)
            {
                items.SetValue(dr["title"].ToString(), i);
                i++;
            }

            return items;
        }

        arr[0] = "";
        return arr;
    }
}

Html side:

<%@ Page Title="" Language="C#" MasterPageFile="~/adminpanel/adminpanel.master" AutoEventWireup="true" CodeFile="autocomplete.aspx.cs" Inherits="adminpanel_autocomplete" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>

    <asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
    <asp:AutoCompleteExtender ID="AutoCompleteExtender1" runat="server"
        MinimumPrefixLength="1" ServiceMethod="testing" ServicePath="WebService.asmx" TargetControlID="TextBox1" Enabled="true">
    </asp:AutoCompleteExtender>
    <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>

Answer 1

I wrote my jQuery AutoComplete handler. So I fixed my question. But still couldn't find the problem about ajax autocomplete extender. Thanks.