Regex IsMatch case-insensitive

C# regex also known as C# regular expression or C# regexp is a sequence of characters that defines a pattern . A pattern may consist of literals, numbers, characters, operators, or constructs. The pattern is used to search strings or files to see if matches are found.

The regular expression pattern is matched in the input string from left to right. Comparisons are case-sensitive . The ^ and $ language elements match the beginning and end of the input string. The end of the input string can be a trailing newline \n character.

If you want only part of the regex to be case insensitive (as my original answer presumed), then you have two options:

The RegexOptions enum is a Regex argument. This example shows how RegexOptions. IgnoreCase affects the result of the IsMatch method on an input that is in a different case . Note When IgnoreCase is specified, the match succeeds. Otherwise it fails.