javascript 调用websevice 内的方法不到 是咋回事？

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Data.SqlClient;
using System.Data;
using Maticsoft.BLL;
/// <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 {

    public WebService () {

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

    [WebMethod]
    public string HelloWorld() 
    {
        
        return "Hello World";
    }
    [WebMethod]
    public string UserLogin(string username,string userpwd,string yzm)
    {
        if (new Maticsoft.BLL.UserInfo().Exists(username))
        {
            DataTable table = new Maticsoft.BLL.UserInfo().GetList(" (UserName='" + username + "' or UserMaill='" + username + "') and UserPwd='" + userpwd + "' ").Tables[0];
            if (table.Rows.Count > 0)
            {
                return "OK";
            }
            else
            {
                return "NO";
            }

        }
        else
        {
            return "用户名不存在";
        }
        
      
    }
    
}