用户控件如何调用WebService.asmx服务里面的方法？

用户控件怎么调用不了服务里的方法呢？下面是我的代码：<%@ Control Language="C#" AutoEventWireup="true" CodeFile="AddArticle.ascx.cs" Inherits="UserControls_AddArticle" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %>                        <table border="0" cellpadding="0" cellspacing="0" width="100%">
                            <tr>
                                <td colspan="3" style="height: 20px;">
                                    <div style="width: 100%;">
                                        <span><font color="gray">(用户可根据职工姓名的</font><font color="#ff6600">首字母</font><font
                                            color="gray">对职工进行筛选添加，也可以直接输入员工姓名进行添加)</font></span>
                                    </div>
                                </td>
                            </tr>
                            <tr>
                                <td style="width: 150px;">
                                    <span style="margin-left: 10px;"><b>请输入筛选条件:</b></span>
                                </td>
                                <td style="width: 300px;">
                                    <asp:UpdatePanel ID="UpdatePanel2" runat="server">
                                        <ContentTemplate>
                                            <asp:TextBox ID="TextBox1" runat="server" Width="300px" Height="20px" Font-Size="Small"></asp:TextBox>
                                            <cc1:AutoCompleteExtender ID="AutoCompleteExtender1" runat="server" TargetControlID="TextBox1"
                                                MinimumPrefixLength="1" ServiceMethod="GetProductName" ScriptPath="WebService.asmx"
                                                CompletionSetCount="10">
                                            </cc1:AutoCompleteExtender>
                                        </ContentTemplate>
                                    </asp:UpdatePanel>
                                </td>
                                <td style="text-align: left; margin-left: 10px;">
                                    <asp:Button runat="server" ID="btnAddUser" Text="添加" Width="60px" Height="20px" Font-Size="Small"
                                        CausesValidation="false" OnClick="btnAddUser_Click" />
                                    <asp:Button runat="server" ID="btnDeleteUser" Text="删除" Width="60px" Height="20px"
                                        Font-Size="Small" CausesValidation="false" OnClick="btnDeleteUser_Click" />
                                    &nbsp;
                                </td>
                            </tr>
                         </table>WebService.asmx的代码using System.Web;
using System.Data;
using System.Collections.Generic;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Data.SqlClient;
using System.Web.Script.Services;
/// <summary>
///WebService 的摘要说明
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
//若要允许使用 ASP.NET AJAX 从脚本中调用此 Web 服务，请取消对下行的注释。 
[ScriptService]
public class WebService : System.Web.Services.WebService
{    public WebService()
    {        //如果使用设计的组件，请取消注释以下行 
        //InitializeComponent(); 
    }[WebMethod]
    [ScriptMethod]
    public string[] GetProductName(string prefixText, int count)
    {
        if (count == 0)
        {
            count = 10;
        } if (prefixText.EndsWith("xyx"))
        {
            return new string[0];
        }
        List<string> suggestions = new List<string>();//声明一泛型集合
        SqlConnection con = new SqlConnection("server=0E69B6B998C74E2\\SQLSERVER2005;database=ComputerWebsite;uid=sa;pwd=123;");
        con.Open();
        SqlCommand com = new SqlCommand("SELECT trueName,userShowName,userSex,userMajor,userClass,userRoomNumber,userMoblie FROM WebUsersDetails JOIN WebUsers ON WebUsersDetails.userID=WebUsers.userID WHERE WebUsersDetails.trueName like '%" + prefixText + "%' or dbo.f_GetTp(WebUsersDetails.trueName) like '%" + prefixText + "%'", con);
        //com.Parameters.Add("@prefixname", SqlDbType.NVarChar).Value = "% '" + prefixText + "' %";
        SqlDataReader sdr = com.ExecuteReader();
        //prefixText = "'%" + prefixText + "%'";
        //DataTable data = CatalogAccess.GetUserUsername(prefixText);
        //List<string> items = new List<string>(data.Rows.Count);
        //for (int i = 0; i < data.Rows.Count; i++)
        //{
        //    items.Add(data.Rows[i]["trueName"].ToString());
        //}
        //return items.ToArray();        while (sdr.Read())
        {
            suggestions.Add(sdr.GetString(0));
        }
        sdr.Close();
        con.Close();
        return suggestions.ToArray();
    }
}
大家帮忙想想啊！这里是用户控件调用WebService.asmx服务的方法