Match Any Character

• . matches any character except line breaks
• . matches any character with api option

_ = new Regex(@".", RegexOptions.Singleline);
// or
_ = new Regex(@"(?s).");

• [\s\S] and [\w\W] and [\d\D] match any character

TIP

Use . only when you really want to allow any character. Use a character class or negated character class in any other situation.

Mode modifier

Use (?s)/(?-s) to enable/disable singleline mode in regex literal