password validation in C#

Password validation in C#

public static bool ValidatePassword(string password, out string ErrorMessage)

{

bool reqUpperCaseLetter = true;

bool reqLowerCaseLetter = false;

bool reqDecimalDigit = false;

bool reqSpecialChar = false;

var input = password;

ErrorMessage = string.Empty;

if (string.IsNullOrWhiteSpace(input))

{

throw new Exception("Password should not be empty");

}

var hasNumber = new Regex(@"[0-9]+");

var hasUpperChar = new Regex(@"[A-Z]+");

var hasMiniMaxChars = new Regex(@".{8,15}");

var hasLowerChar = new Regex(@"[a-z]+");

var hasSymbols = new Regex(@"[!@#$%^&*()_+=\[{\]};:<>|./?,-]");

if (!hasLowerChar.IsMatch(input) && reqLowerCaseLetter ==true)

{

ErrorMessage = "Password should contain at least one lower case letter.";

return false;

}

else if (!hasUpperChar.IsMatch(input) && reqUpperCaseLetter ==true)

{

ErrorMessage = "Password should contain at least one upper case letter.";

return false;

}

else if (!hasMiniMaxChars.IsMatch(input))

{

ErrorMessage = "Password should not be lesser than 8 or greater than 15 characters.";

return false;

}

else if (!hasNumber.IsMatch(input) && reqDecimalDigit==false)

{

ErrorMessage = "Password should contain at least one numeric value.";

return false;

}

else if (!hasSymbols.IsMatch(input) && reqSpecialChar ==false)

{

ErrorMessage = "Password should contain at least one special case character.";

return false;

}

else

{

ErrorMessage = "Success";

return true;

}