c# - a regex pattern that never matches anything -

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this question has answer here:

i'm maintaining c# software contains list of rules , each rule has regex pattern part of definition. regex pattern determines whether rule should applied particular data instance or not.

i.e. given particular string, apply rule if regex pattern matches against string, never apply rule against strings regex pattern not match.

i deactivate rules never apply against string.

so need regex pattern not match, no matter string value passed it.

any suggestions?

a negative lookahead looks nothingness not follow current position: (?!)


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