I have a single RequiredFieldValidator attached to a TextBox. It is in a ValidationGroup with the buttons that will require it to be validated.
<tr>
<td width="300" style="font-family: Calibri, Arial" align="left">Agency:</td>
<td width="500" style="font-family: Calibri, Arial">
<asp:TextBox ID="Agency" runat="server" Text='<%# Bind("Agency") %>' Width="450px"></asp:TextBox>
<asp:RequiredFieldValidator ID="Agency_RequiredFieldValidator" ControlToValidate="Agency" EnableClientScript="true" ValidationGroup="Val" runat="server" ErrorMessage="Agency">
</asp:RequiredFieldValidator></td>
</tr>
<asp:Button ID="btnSave" runat="server" Text="Save Program" Width="150px" C ...
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