Hi Jagadeesh,
First of all let you know that you can not add this kind of conditions within a tag of any control.
What you can do here is you can generate controls as per the satisfaction of the condition as mentioned in below example :-
Ex :-
<% if (!IsToView)
{ %>
<asp:RadioButton ID="RadioButton1" runat="server" GroupName="Options" Text='test' />
<% } %>
<% else { %>
<asp:RadioButton ID="RadioButton2" runat="server" GroupName="Options" Text='test' Checked="true" />
<% } %>
This just an example to help you out.
Hope this will be surely helpful to you .