ASP Control - Change Attribute Dynamically from VB.Net result

not sure if i understand, you want to access the attributes of a textbox control?

if so you can do this on codebehind:
HomePhone.Attribute.Add("MyAttribute","something")
you can also remove attributes:
HomePhone.Attribute.Remove("MyAttribute")

I'm not using a codebehind page. How would I do that just wrapped in <%  %>

If the control is blank then 'errormsg' is populated:

<%
    If Request.Form("submit") = "Next" Then
        Dim is_ok = True
        If Request.Form("HomePhone") = "" Then
            is_ok = False
            errormsg = errormsg & "Home Phone is required<br />"
        End If
%>

The user returns to the form and that error message is written out above the form.

I also want to 'light up' the Home Phone control so the user can easily focus on it. There is other required information as well gathered in the form.

This is obviously incorrect, but shows want I want to do:
<td><asp:TextBox ID="HomePhone" MaxLength="12" runat="server" TabIndex="4" <%If not errormsg = "" Then %>BorderColor="#990033"<%End If %> /></td>

Just trying to find out how to do this correctly.

Thanks!!

try this code below

HomePhone.Attributes.Add("value", "your dynamic content");

<script type = "text/javascript">
<!--
function hide(x) {
document.getElementById(x).style.display='none';
document.getElementById(x).value='';
}
function show(x) {
document.getElementById(x).style.display='';
}
//-->
</script>