Using AutoCompleteExtender in asp.NET

//SERVICE  Example: extenderService.asmx

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

/// <summary>
/// Summary description for AutoCompleteService
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[System.Web.Script.Services.ScriptService]
// To allow this Web Service to be called from script, using ASP.NET AJAX,
uncomment the following line.