请教,小弟我在JS中给这个赋值.

请问,我在JS中给这个赋值.....
请问,我在JS中给这个赋值,
<input   id= "Text2 "   type= "text "   runat= "server "   />
可ID到了客户端成了ctl00_ContentPlaceHolder1_Text2,
document.getElementById( "Text2 ").value=result;要怎么写啊?
ctl00_ContentPlaceHolder1_Text2是随机生成的吗?

------解决方案--------------------------------------------------------
document.getElementById( " <%=Text2.ClientID%> ").value
------解决方案--------------------------------------------------------
document.getElementById( "Text2 ").value=result;
改为：
document.getElementById( " <%= Text2.ClientID %> ").value=result;
------解决方案--------------------------------------------------------
<script type= "text/jscript " language= "javascript ">
function test()
{
var t;
t=document.getElementById( " <%=TextBox1.ClientID%> ")
alert(t.value)
}
</script>