I have 2 back to back checkboxlist and I need to make sure the user selects one from each list. How can I validate a checkboxlist?
<tr>
<td class="NavyBold">Please Select age group:</td>
<td><asp:checkboxlist id="chkagegrp" Runat="server" RepeatDirection="Horizontal" RepeatColumns="4" AutoPostBack="false">
<asp:ListItem Value="Twenties"></asp:ListItem>
<asp:ListItem Value="Thirties"></asp:ListItem>
<asp:ListItem Value="Forties"></asp:ListItem>
</asp:checkboxlist></td>
</tr>
<tr>
<td class="NavyBold">Please Select A Favorite Sport:</td>
<td><asp:checkboxlist id="chkfavsprt" Runat="server" RepeatDirection="Vertical" RepeatColumns="2" AutoPostBack="false">
<asp:ListItem Value="Tennis"></asp:ListItem>
<asp:ListItem Value="Soccer"></asp:ListItem>
<asp:ListItem Value="Fotball"></asp:ListItem>
</asp:checkboxlist></td>
</tr>
<tr>
<td class="NavyBold">Please Select age group:</td>
<td><asp:checkboxlist id="chkagegrp" Runat="server" RepeatDirection="Horizontal" RepeatColumns="4" AutoPostBack="false">
<asp:ListItem Value="Twenties"></asp:ListItem>
<asp:ListItem Value="Thirties"></asp:ListItem>
<asp:ListItem Value="Forties"></asp:ListItem>
</asp:checkboxlist></td>
</tr>
<tr>
<td class="NavyBold">Please Select A Favorite Sport:</td>
<td><asp:checkboxlist id="chkfavsprt" Runat="server" RepeatDirection="Vertical" RepeatColumns="2" AutoPostBack="false">
<asp:ListItem Value="Tennis"></asp:ListItem>
<asp:ListItem Value="Soccer"></asp:ListItem>
<asp:ListItem Value="Fotball"></asp:ListItem>
</asp:checkboxlist></td>
</tr>