版本为AJAX November CTP
 三个示例分别为:
1 带参数的WS方法
2 不带参数的WS方法
3 参数类型为DataTable的WS方法
 一、WebMethod
注意要点:
1 WebMethod类需要添加命名空间 Microsoft.Web.Script.Services,此空间需要引用Microsoft.Web.Preview.dll
2 类声明加入标签 [ScriptService]
3 在Asp.net 2.0里可以直接用DataTable作为返回类型了,但是需要在Web.config文件添加序列化转换器的属性。DataSet、DataTable、DataRow均有转换器
 <system.web.extensions>
    <scripting>
      <webServices>
        <jsonSerialization>
          <converters>
            <add name="DataSetConverter" type="Microsoft.Web.Preview.Script.Serialization.Converters.DataSetConverter, Microsoft.Web.Preview"/>
            <add name="DataRowConverter" type="Microsoft.Web.Preview.Script.Serialization.Converters.DataRowConverter, Microsoft.Web.Preview"/>
            <add name="DataTableConverter" type="Microsoft.Web.Preview.Script.Serialization.Converters.DataTableConverter, Microsoft.Web.Preview"/>
          </converters>
        </jsonSerialization>
      </webServices>
    </scripting>
</system.web.extensions>
WEB服务1:WS1
 using System;
using System.Web;
using System.Collections;
using System.Web.Services;
using System.Web.Services.Protocols;
using Microsoft.Web.Script.Services;
using System.Data;
/** <summary>
/// WS1 的摘要说明
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[ScriptService]
public class WS1 : System.Web.Services.WebService {
     public WS1 () {
         //如果使用设计的组件,请取消注释以下行 
        //InitializeComponent(); 
    }
     [WebMethod]
    public string ServerTime()
    {
        return String.Format("now: {0}", DateTime.Now);
    }
     [WebMethod]
    public DataTable GetDataTable()
    {
        DataTable dt = new DataTable("Person");
         dt.Columns.Add(new DataColumn("Name", typeof(string)));
        dt.Columns.Add(new DataColumn("LastName", typeof(string)));
        dt.Columns.Add(new DataColumn("Email", typeof(string)));
         dt.Rows.Add("kui", "he", "hekui168@163.com");
        dt.Rows.Add("ren", "chao", "chaoren888@163.com");
         return dt;
    }
}
 
WEB服务2:WS
 using System;
using System.Web;
using System.Collections;
using System.Web.Services;
using System.Web.Services.Protocols;
using Microsoft.Web.Script.Services;
 /** <summary>
/// WS 的摘要说明
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[ScriptService]
public class WS : System.Web.Services.WebService {
     public WS () {
         //如果使用设计的组件,请取消注释以下行 
        //InitializeComponent(); 
    }
     [WebMethod]
    [ScriptMethod(UseHttpGet = true)]
    public string HelloWorld(String query)
    {
        string inputString = Server.HtmlEncode(query);
        if (!String.IsNullOrEmpty(inputString))
        {
            return String.Format("hello, {0}. ", inputString);
        }
        else
        {
            return "query string is null or empty";
        }
    }
 }
 
二、前台页面:
注意要点:
需要使用的后台WebService的方法均设置在如下位置
         <asp:ScriptManager ID="ScriptManager1" runat="server">
            <Services>
                <asp:ServiceReference Path="~/WS.asmx" />
                <asp:ServiceReference Path="~/WS1.asmx" />
            </Services>
        </asp:ScriptManager>
Default页面:
 <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>Untitled Page</title>
     <script language="javascript" type="text/javascript" src="js.js">
    </script>
 </head>
<body>
    <form id="form1" runat="server">
        <asp:ScriptManager ID="ScriptManager1" runat="server">
            <Services>
                <asp:ServiceReference Path="~/WS.asmx" />
                <asp:ServiceReference Path="~/WS1.asmx" />
            </Services>
        </asp:ScriptManager>
        <div>
            <asp:Button ID="Button1" runat="server" Text="Button" OnClientClick="dd();return false;" />
            <div id="time">
            </div>
            <div id="List1">
                <asp:DropDownList ID="ddl1" runat="server" Width="187px">
                </asp:DropDownList>
                </div>
            
        </div>
    </form>
</body>
</html>
 三、JavaScript程序:
注意要点:
AJAX November CTP 需要用 eval() 方法将其转换成一个DataTable对象(并且要裁掉最前面的"("),而AJAX December CTP 支持以下方法转换“Sys.Preview.Data.DataTable.parseFromJson(result)”
     function dd()
    {
        WS.HelloWorld(   
                         'hekui', 
                         function(result) 
                         { 
                            alert(result); 
                         } 
                     );
        WS1.ServerTime( 
                         function(result) 
                         { 
                            alert(result); 
                            var divTime = document.getElementById("time");
                            divTime.innerHTML = result;
                         } 
                     );
       WS1.GetDataTable(
                         function(result) 
                         {
                            // 获取到下拉框控件
                            var List = document.getElementById("ddl1"); 
                                                       
                            //AJAX November CTP 需要用 eval() 方法将其转换成一个DataTable对象(并且要裁掉最前面的"(")
                            var Text= result.dataArray.substring(0,result.dataArray.length -1);            
                            var Table = eval( Text);
                            
                            //AJAX December CTP 支持以下方法转换
//                            var Table = Sys.Preview.Data.DataTable.parseFromJson(result);
                            
                            //清除下拉框原有列表项
                            for (x=List.options.length-1; x > -1; x--) 
                            {
                                List.remove(0);
                            }
                            
                            //从获取的DataTable添加数据到下拉框列表项
                            for (x=0; x < Table.length; x++ )
                            {
                                //获取每一行
                                var Row = Table[x];          
                                //创建一个列表项                  
                                var option = document.createElement("option"); 
                                //列表项显示文本赋值
                                option.text = Row.Name + " " + Row.LastName;   
                                //列表项选项值赋值
                                option.value = Row.Email;                      
                                 //判断浏览器类型,进行项目添加     
                                if ( window.navigator.appName.toLowerCase().indexOf("microsoft") > -1) 
                                   List.add(option); 
                                else
                                   List.add(option, null);          
                            }
                         }
                       );
    }