If by active you mean only one of them can be checked, you don't need code for that. HTML knows how to do that already.
Assuming you are talking about an asp.NET page here, just use an <asp:radiobuttonlist> on your page.
If you are talking about raw HTML, just set the name attribute of each radio button to the same value.
Assuming you are talking about an asp.NET page here, just use an <asp:radiobuttonlist> on your page.
If you are talking about raw HTML, just set the name attribute of each radio button to the same value.