How do you use in regular expression in asp.net simple?

In ASP.NET, you can use regular expressions through the System.Text.RegularExpressions namespace. To utilize regex, instantiate the Regex class with your pattern and use methods like IsMatch, Match, or Replace to validate or manipulate strings. For example, to check if a string matches a pattern, you can use: bool isMatch = Regex.IsMatch(inputString, pattern);. Additionally, you can incorporate regex in validation controls within ASP.NET Web Forms or MVC by setting the RegularExpression attribute.