Serverside custom validator
Instead of hacking Javascript based client scripts for input validation you might consider server side custom validation. Stick to C# and be happier.
<asp:CustomValidator ID="valTemplate" ControlToValidate ="epiTemplate"
OnServerValidate="ServerValidate" display="Dynamic" runat="server" />
protected void ServerValidate(object source, ServerValidateEventArgs args)
{
args.IsValid = false;
valTemplate.ErrorMessage = "This is bad!";
}