Is it possible to assign Multiple Validation Groups to a single Validation Control?

Question

I have a Form like this.

UserID has to be validated when user clicks "Check Availability" and "Submit"

Hence "UserID" required field validator has to be assigned two grops.

As if now it is assigned only Group1

 <asp:RequiredFieldValidator ID="UserIDRequiredFieldValidator" runat="server" ErrorMessage="Enter UserID"
                    ControlToValidate="txtUserID" ValidationGroup="Group1"></asp:RequiredFieldValidator>

So is it possible to assign "Group1" and "Group2" to UserIDRequiredFieldValidator

I have already gone through How to validate against Multiple validation groups? which talks about validating Group1 and Group2 when user clicks "Submit" which is a good alternate solution .

Thanks in Advance

Answer 1

What about using two RequiredFieldValidator objects, one for Group1 and one for Group2?