test.aspx.cs
Search.Attributes.Add("onkeydown","return confrm();");
test.aspx
<script>
function confrm()
{
if(event.keyCode==13)
{
if(Form1.Search.value=="")
{
alert('检索不能为空');
Form1.Search.focus();
return false;
}
document.all.Button2.click();
return false;
}
}
}
</script>