What is the regular Expression Validation for only Letters and Numbers in asp.net? I need to enter first two should be character after that it can take hyphen(\[code\]-\[/code\]), space(\[code\]\[/code\]), apostrophes(\[code\]'\[/code\])I tried\[code\]^[A-Z a-z\s-'\s]{2,25}$\[/code\]this is not working.