The
Digital Input Example earlier on the page shows how to open a digital input in Begin.
Really, it's the same way you open and use any hardware resource using the WPI library. The built-in FRC examples and tutorials and LabVIEW help should be good enough to help you do this. At what point are they losing you? Where does it not give the detail you need in order to follow it? Your input can help make the documentation better.
If you want an explanation of how it works,
http://www.chiefdelphi.com/forums/sh...d.php?t=134319 is a recent thread about limit switches. The Search feature of the Chief Delphi forums can help you find others.