c# - Regex for rejecting specified strings

Question

I have to use asp.net RegularexpressionValidator to validate input from textbox. I want to reject strings that start with "My Links" or "My Urls" I have used this

   ^(?!My Links|My Urls)$

but this rejects everything. How should I write this?

Answer 1

If your goal is to reject all strings that start with My Links or My Urls, then you can use lookaheads, but only if you remove the $ at the end, or only the empty string will match:

^(?!My Links|My Urls)

works as expected.