select 1 radiobuton and show the sem 1&2 only

Question

choose one radio button and show the semester as 1 and 2 only 

 

 

<tr><td><asp:Label ID="Lafbel6" runat="server" Text="Year" ForeColor="BLACK"></asp:Label></td><td>

<asp:RadioButton ID="r1" runat="server" Text="Ist Year" AutoPostBack="True" oncheckedchanged="r1_CheckedChanged" /><asp:RadioButton ID="r2" runat="server" Text="IInd Year" AutoPostBack="True" oncheckedchanged="r2_CheckedChanged" /><asp:RadioButton ID="r3" runat="server" Text="IIIrd Year" AutoPostBack="True" oncheckedchanged="r3_CheckedChanged" /><br /></td></tr>

<tr><td><asp:Label ID="Label7" runat="server" Text="Semester" ForeColor="BLACK"></asp:Label></td><td><asp:CheckBox ID="c1" runat="server" Text="I "/><asp:CheckBox ID="c2" runat="server" Text="II"/><asp:CheckBox ID="c3" runat="server" Text="III"/>

<asp:CheckBox ID="c4" runat="server" Text="IV"/><asp:CheckBox ID="c5"

runat="server" Text="V"/><asp:CheckBox ID="c6" runat="server" Text="VI" /></td></tr>