Many applications write various information into log files and sometimes this information is sensitive, e.g. contains user passwords. In my case, I knew that we are logging SQL statements with stored procedures calls and one of the parameters may contain user’s password. So I have been asked to replace such passwords with something neutral. I’ve ended with following regular expression string (works only for stored procedures and alike call logs!): (?<Pre>(pass(word)?|pwd)[^=']*=[^']*'?)(?<Target>[^']+)(?<Post>'?) Technorati Tags: Regular Expressions, CSHarp, C#