关于回车触发按钮事件

网页中只有一个TextBox的时候，当TestBox中输入文字，习惯性按下回车提交时，页面只会刷新一下，并没有将TextBox中的内容提交。如：

< asp:TextBox id = " tbInput "  runat = " server "  Width = " 240px " ></ asp:TextBox >
< asp:Button id = " btnOK "  runat = " server "  BorderWidth = " 1px "  BorderColor = " Purple "  BorderStyle = " Solid "  Text = " Search Site " ></ asp:Button >

以前找到一个方案，用javascript来解决。添加：
< SCRIPT LANGUAGE = " javascript " >
<!--
function SubmitKeyClick(button) 
{    
 if (event.keyCode == 13) 
 {        
  event.keyCode=9;
  event.returnValue = false;
  document.all[button].click(); 
 }
}
//  -->
</ SCRIPT >
Page_Load里添加：
tbInput.Attributes.Add( " onkeydown " , " SubmitKeyClick('btnOK'); " );
另一个解决办法是添加一个TextBox，style设置成隐藏的就可以了（Visible设置成false是不行的）。
< asp:TextBox id = " tbInput "  runat = " server "  Width = " 240px " ></ asp:TextBox >
< asp:TextBox id = " hidden "  runat = " server "  style = " visibility:hidden;display:none; " ></ asp:TextBox >
< asp:Button id = " btnOK "  runat = " server "  BorderWidth = " 1px "  BorderColor = " Purple "  BorderStyle = " Solid "  Text = " Search Site " ></ asp:Button >