public static string mytest(string first, string second) 
{ 
  return return first+second; 
} 

<form id="myform" runat="server"> 
<div> 
 <asp:Button ID="bt" runat="server" Text="点击测试" /> 
</div> 
</form> 

$(function(){ 
 $("#bt").click(function(){ 
  $.ajax({ 
   type:"Post", 
   url:"antzone.aspx/mytest", 
   data:"{'first':'蚂蚁部落','second':'欢迎您'}", 
   contentType:"application/json;charset=utf-8", 
   dataType:"json", 
   success:function(data){ 
    //返回的数据用data.d获取内容 
    alert(data.d); 
   }, 
   error:function(err){ 
    alert(err); 
   } 
  }); 
  //禁用按钮的提交 
  return false; 
 }); 
});