Programmers Stack Exchange is a question and answer site for professional programmers interested in conceptual questions about software development. Join them; it only takes a minute:
Here's how it works:
- Anybody can ask a question
- Anybody can answer
- The best answers are voted up and rise to the top
You can use a PopUpControlExtender, which is part of the ASP.NET Ajax library. There's a modal popup version as well.