static void Main(string[] args)
{
{
var opts = new RandomPasswordOptions()
{
AtLeastOneNumber = true,
AtLeastOneSpecial = false,
AtLeastOneUppercase = true,
Length = 8,
AvoidChars = new[] { 'l', 'I', 'O', '0' }
};
var pass = RandomPassword(opts);
System.Console.WriteLine($"pass [{pass}] in {opts.LoopCount} loop count");
}
{
var opts = new RandomPasswordOptions()
{
AllowLetter = false,
AtLeastOneUppercase = false,
Length = 4
};
var pass = RandomPassword(opts);
System.Console.WriteLine($"pin [{pass}] in {opts.LoopCount} loop count");
}
}
/// <summary>
/// Generates the password.
/// </summary>
/// <returns></returns>
private static string GeneratePassword(int passwordLength,
RandomPasswordOptions option)
{
if (passwordLength < 0)
{
return(null);
}
var passwordChars = GetCharacters(option);
if (string.IsNullOrEmpty(passwordChars))
{
return(null);
}
var password = new char[passwordLength];
var random = GetRandom();
for (int i = 0; i < passwordLength; i++)
{
var index = random.Next(passwordChars.Length);
var passwordChar = passwordChars[index];
password[i] = passwordChar;
}
return(new string(password));
}
/// <summary>
/// Gets the characters selected by the option
/// </summary>
/// <returns></returns>
private string GetCharacters(RandomPasswordOptions option)
{
switch (option) {
case RandomPasswordOptions.Alpha:
return PASSWORD_CHARS_Alpha;
case RandomPasswordOptions.Numeric:
return PASSWORD_CHARS_NUMERIC;
case RandomPasswordOptions.AlphaNumeric:
return PASSWORD_CHARS_Alpha + PASSWORD_CHARS_NUMERIC;
case RandomPasswordOptions.AlphaNumericSpecial:
return PASSWORD_CHARS_Alpha + PASSWORD_CHARS_NUMERIC +
PASSWORD_CHARS_SPECIAL;
default:
break;
}
return string.Empty;
}
/// <SUMMARY>
/// Gets the characters selected by the option
/// </SUMMARY>
/// <RETURNS></RETURNS>
private static string GetCharacters(RandomPasswordOptions option)
{
switch (option)
{
case RandomPasswordOptions.Alpha:
return(PASSWORD_CHARS_Alpha);
case RandomPasswordOptions.Numeric:
return(PASSWORD_CHARS_NUMERIC);
case RandomPasswordOptions.AlphaNumeric:
return(PASSWORD_CHARS_Alpha + PASSWORD_CHARS_NUMERIC);
case RandomPasswordOptions.AlphaNumericSpecial:
return(PASSWORD_CHARS_NUMERIC); //PASSWORD_CHARS_Alpha + PASSWORD_CHARS_NUMERIC + PASSWORD_CHARS_SPECIAL;
}
return(string.Empty);
}
/// <SUMMARY>
/// Generates the password.
/// </SUMMARY>
/// <RETURNS></RETURNS>
private static string GeneratePassword(int passwordLength,
RandomPasswordOptions option)
{
if (passwordLength < 0) return null;
var passwordChars = GetCharacters(option);
if (string.IsNullOrEmpty(passwordChars)) return null;
var password = new char[passwordLength];
var random = GetRandom();
for (int i = 0; i < passwordLength; i++)
{
var index = random.Next(passwordChars.Length);
var passwordChar = passwordChars[index];
password[i] = passwordChar;
}
return new string(password);
}
/// <summary>
/// Generates a random password.
/// </summary>
/// <returns>Randomly generated password.</returns>
public string Generate(int passwordLength = DEFAULT_PASSWORD_LENGTH,
RandomPasswordOptions option = RandomPasswordOptions.AlphaNumericSpecial)
{
if (passwordLength < 0)
return null;
var passwordChars = GetCharacters (option);
if (string.IsNullOrEmpty (passwordChars))
return null;
var password = new char[passwordLength];
var random = GetRandom ();
for (int i = 0; i < passwordLength; i++) {
var index = random.Next (passwordChars.Length);
var passwordChar = passwordChars [index];
password [i] = passwordChar;
}
return new string (password);
}
/// <SUMMARY>
/// Generates a random password.
/// </SUMMARY>
/// <RETURNS>Randomly generated password.</RETURNS>
public static string Generate(int passwordLength, RandomPasswordOptions option)
{
return(GeneratePassword(passwordLength, option));
}
/// <summary>
/// Generates a random password with the default length.
/// </summary>
/// <returns>Randomly generated password.</returns>
public string Generate(RandomPasswordOptions option)
{
var rdn = new Random(DateTime.Now.Millisecond);
return(Generate(rdn.Next(8, 99), option));
}
/// <summary>
/// Generates a random password with the default length.
/// </summary>
/// <returns>Randomly generated password.</returns>
public static string Generate(RandomPasswordOptions option)
{
return(Generate(DEFAULT_PASSWORD_LENGTH, option));
}
/// <summary>
/// Generate random password using defaults ( allow numbers, lowercase, uppercase, 12 of length, no special symbol )
/// </summary>
public static string RandomPassword(RandomPasswordOptions opts = null)
{
if (opts == null)
{
opts = new RandomPasswordOptions();
}
var sb = new StringBuilder();
var rnd = new Random();
var loopCount = 0;
{
var cntRequired = 0;
if (opts.AtLeastOneNumber)
{
++cntRequired;
}
if (opts.AtLeastOneSpecial)
{
++cntRequired;
}
if (opts.AtLeastOneUppercase)
{
++cntRequired;
}
if (cntRequired > opts.Length)
{
throw new ArgumentException($"invalid length not enough for required at least {cntRequired} characters");
}
if (opts.Length == 0)
{
throw new ArgumentException($"invalid 0 length");
}
}
while (true)
{
if (loopCount > 100)
{
throw new Exception($"unable to find suitable password in {loopCount} step");
}
++opts.LoopCount;
sb.Clear();
var specialCount = 0;
var numberCount = 0;
var uppercaseCount = 0;
while (sb.Length < opts.Length)
{
var n = rnd.Next(48, 122);
var c = Convert.ToChar(n);
if (opts.AvoidChars != null && opts.AvoidChars.Any(a => c == a))
{
continue;
}
if (char.IsNumber(c) && (opts.AllowNumber || (opts.AtLeastOneNumber && numberCount == 0)))
{
sb.Append(c);
++numberCount;
}
else if (char.IsLetter(c) && opts.AllowLetter)
{
if (char.IsLower(c) && opts.AllowLowercase)
{
sb.Append(c);
}
else if (opts.AllowUppercase || (opts.AtLeastOneUppercase && uppercaseCount == 0))
{
sb.Append(c);
++uppercaseCount;
}
}
else if (specialCount < opts.MaxSpecial && (opts.AllowSpecial || (opts.AtLeastOneSpecial && specialCount == 0)))
{
sb.Append(c);
specialCount++;
}
}
if (opts.AtLeastOneNumber && numberCount == 0)
{
continue;
}
if (opts.AtLeastOneSpecial && specialCount == 0)
{
continue;
}
if (opts.AtLeastOneUppercase && uppercaseCount == 0)
{
continue;
}
break;
}
return(sb.ToString());
}
/// <SUMMARY>
/// Generates a random password.
/// </SUMMARY>
/// <RETURNS>Randomly generated password.</RETURNS>
public static string Generate(int passwordLength,
RandomPasswordOptions option)
{
return GeneratePassword(passwordLength, option);
}
/// <SUMMARY>
/// Generates a random password with the default length.
/// </SUMMARY>
/// <RETURNS>Randomly generated password.</RETURNS>
public static string Generate(RandomPasswordOptions option)
{
return Generate(DEFAULT_PASSWORD_LENGTH, option);
}
