客户端访问PageMethods

//前台代码

  <form id="form1" runat="server">
        <asp:ScriptManager ID="ScriptManager1" runat="server" EnablePageMethods="true" />
        
        <input type="button" value="Get Current Time" onclick="getCurrentTime()" />
    
        <script language="javascript" type="text/javascript">
            function getCurrentTime()
            {
                PageMethods.GetCurrentTime(getCurrentTimeSucceeded);
            }
            
            function getCurrentTimeSucceeded(result)
            {
                alert(result);
            }
        </script>
    </form>

//后台代码

    [WebMethod]
    public static DateTime GetCurrentTime()
    {
        return DateTime.UtcNow;
    }