Email Address Validation Using Regular Expression

public static class TestEmail
{
  /// <summary>
  /// Regular expression, which is used to validate an E-Mail address.
  /// </summary>
  public const string MatchEmailPattern = 
    		@"^(([\w-]+\.)+[\w-]+|([a-zA-Z]{1}|[\w-]{2,}))@"
     + @"((([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\.([0-1]?
				[0-9]{1,2}|25[0-5]|2[0-4][0-9])\."
     + @"([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\.([0-1]?
				[0-9]{1,2}|25[0-5]|2[0-4][0-9])){1}|"
     + @"([a-zA-Z]+[\w-]+\.)+[a-zA-Z]{2,4})$";

  /// <summary>
  /// Checks whether the given Email-Parameter is a valid E-Mail address.
  /// </summary>
  /// <param name="email">Parameter-string that contains an E-Mail address.</param>
  /// <returns>True, when Parameter-string is not null and 
  /// contains a valid E-Mail address;
  /// otherwise false.</returns>
  public static bool IsEmail(string email)
  {
     if (email != null) return Regex.IsMatch(email, MatchEmailPattern);
     else return false;
  }
}        

참조 : http://www.codeproject.com/Articles/22777/Email-Address-Validation-Using-Regular-Expression