This is a great idea - an ASP.NET server control that only shows if popups are blocked. Use it to show a warning message, info on how to disable popup blocking for your site, or the information you would have shown in the popup if it was allowed.
Now that all the browsers are including popup blockers, this kind of thing should be required in pages that still use popups.
[...] The PopupTester control is derived from Panel, which means that it is a container control to which you can simply add whatever other controls you want to display if a popup blocker is found.
Add an instance to your aspx page with
<mbw:PopupTester id="popupTester" runat="server">Popups are being blocked</mbw:PopupTester>
Again, you are free to place whatever content you like inside the PopupTester control. The control will render with a style of display:none, unless a popup blocker is found. If one is found, it renders with display:block. This control should work with Netscape, Internet Explorer and FireFox.
If you're using popups in an ASP.NET application, you owe it to your users to give this control a shot. There is no cost, so what do you have to lose?
If you are using this, Id love to hear your thoughts about it...