Validating Gender Dynamically using REGEX

Introduction

Given that you will likely need to have the gender in an enumerated value anyway, I would simply use what's built into the .NET enum class. Something as simple as the following may be all you need.

public enum Gender
{
  Unknown = 0
,
  Female = 1
,
  F = Female
,
  Male = 2
,
  M = Male
}

Gender g ;
if ( System.Enum.TryParse ( s , true , out g ) ) ...