Regex to match anything but two words

.net regex regex-negation
goombaloon picture goombaloon · Jul 26, 2011 · Viewed 53.1k times · Source

I'm trying to write a regular expression to match anything that isn't "foo" and "bar". I found how to match anything but one word at Regular expression to match a line that doesn't contain a word? but I'm not very skilled with regex and am unsure of how to add a second word to this critera.

Any help would be most appreciated!

CLARIFICATION:

I wanted to match on anything that wasn't EXACTLY foo or bar.

Answer

Tim Pietzcker picture Tim Pietzcker · Jul 26, 2011

Answer to the question: "A Regular Expression to match anything that isn't "foo" and "bar"?"

^(?!foo$|bar$).*

would do exactly that.

^      # Start of string
(?!    # Assert that it's impossible to match...
 foo   # foo, followed by
 $     # end of string
|      #
 bar$  # bar, followed by end of string.
)      # End of negative lookahead assertion
.*     # Now match anything

You might need to set RegexOptions.Singleline if your string can contain newlines that you also wish to match.

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