how to capture keypress or keydown in textbox using asp.net with c#.net. can any one give me some help

The keypress event is client side(javascript) event. You cannot handle it in C#.
But if you want to execute some server side code in keypress event, then handle the client side keypress event and call a web service in it.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.