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 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.

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: