[RESOLVED] Adding onKeyPress programmatically

I have web app using C# and ASP.Net. I want to add a onKeyPress programmatically to an textbox and when user is typing call a C# function to reset the session time out. I have tried in Javascript but it does not recognize Session.Timeout. Also I have added onKeyPress successfully but can not get the call to a C# routine right.

Can this be done in C#?

C# would be used for server side coding. Session is also a server side object. Java Script is used for Client side coding so it has no access to the Session object. The problem is that you want to access a server side object from the client side which you can not do.