A more comprehensive validator
Simple enough and easy to implement credit card validator
Straightforward article on using NUnit within .Net
Nice intro to the .Net build tool NAnt
Very good article on handling .Net exceptions
Series of article on continuous integration.
Nice article on setup of Cruise control
Article on getting .net to play with COM
Article on getting .net to play with COM
Article on getting .net to play with COM
Nice little framework for ASP .net error / exception handling. This is quite a comprehensive article with plenty of detail - might take you a few hours to implement.
Some interesting looking components for the ASP.net platform.
Nice straightforward article on using isInteger - and other options.
Short description of using the .Net obfuscator in Visual studio
Encrypting the web.config on .Net
Encryption of the web.config in .Net
Article on encrypting the web.config with some good links.
Simple approach to error logging in .Net by just writing to files.
Some nice simple examples on how you might log errors.
No quite error handling, but usesful tips on how to find errors in asp .Net pages.