private async Task <double> ReadNumber(char c0)
{
bool hasDecimal = false;
const string NUMBERS = "0123456789.";
var sb = new StringBuilder();
char c = c0;
while (true)
{
if (c == '.')
{
if (hasDecimal)
{
throw new FormatException("Invalid number; only one decimal point is allowed");
}
else
{
hasDecimal = true;
}
}
sb.Append(c);
try
{
c = await ReadNextChar();
}
catch (EndOfStreamException)
{
break;
}
if (!NUMBERS.Contains(c))
{
UnreadChar(c);
break;
}
}
return(double.Parse(sb.ToString()));
}
/// <summary>
///
/// </summary>
/// <returns></returns>
public static string GenerateRawPassword()
{
const int MAXIMUM_IDENTICAL_CONSECUTIVE_CHARS = 2;
const string SMALL_LETTERS = "abcdefghijklmnopqrstuvwxyz";
const string CAPTAL_LETTERS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const string NUMBERS = "0123456789";
const string SPECIAL_LETTERS = @"!#$%&*@\";
//random possible character pool
List <string> CHARACTER_ARRAY = new List <string> {
SMALL_LETTERS, CAPTAL_LETTERS, NUMBERS, SPECIAL_LETTERS
};
//character pool to generate raw password.
string characterSet = "";
//get 3 types from random pool
System.Random random = new System.Random();
CHARACTER_ARRAY.RemoveAt(random.Next(0, 3));
for (int i = 0; i < 3; i++)
{
characterSet += CHARACTER_ARRAY[i];
}
//raw password holder
char[] password = new char[8];
for (int characterPosition = 0; characterPosition < 8; characterPosition++)
{
password[characterPosition] = characterSet[random.Next(characterSet.Length - 1)];
bool moreThanTwoIdenticalInARow =
characterPosition >= MAXIMUM_IDENTICAL_CONSECUTIVE_CHARS &&
password[characterPosition] == password[characterPosition - 1] &&
password[characterPosition - 1] == password[characterPosition - 2];
if (moreThanTwoIdenticalInARow)
{
characterPosition--;
}
}
//check if 8 random characters are 3 different types
int SMALL_LETTER_COUNT = 0;
int CAPITAL_LETTER_COUNT = 0;
int NUMBER_COUNT = 0;
int SPECIAL_LETTER_COUNT = 0;
//Cout each type
for (int i = 0; i < password.Length; i++)
{
if (SMALL_LETTERS.Contains(password[i]))
{
SMALL_LETTER_COUNT++;
}
else if (CAPTAL_LETTERS.Contains(password[i]))
{
CAPITAL_LETTER_COUNT++;
}
else if (NUMBERS.Contains(password[i]))
{
NUMBER_COUNT++;
}
else if (SPECIAL_LETTERS.Contains(password[i]))
{
SPECIAL_LETTER_COUNT++;
}
}
List <string> LEFT_RANDOM = new List <string>();
if (SMALL_LETTER_COUNT == 0)
{
LEFT_RANDOM.Add(SMALL_LETTERS);
}
if (CAPITAL_LETTER_COUNT == 0)
{
LEFT_RANDOM.Add(CAPTAL_LETTERS);
}
if (NUMBER_COUNT == 0)
{
LEFT_RANDOM.Add(NUMBERS);
}
if (SPECIAL_LETTER_COUNT == 0)
{
LEFT_RANDOM.Add(SPECIAL_LETTERS);
}
string str_password = new string(password);
if (LEFT_RANDOM.Count > 1)
{
//get random Character set wheren count = 0
string leftcharSet = LEFT_RANDOM[random.Next(LEFT_RANDOM.Count)];
//replace last character with another random character
str_password = str_password.Remove(7, 1) + leftcharSet[random.Next(leftcharSet.Length - 1)].ToString();
}
return(str_password);
}
public static string Generate6DigitPassword()
{
const int MAXIMUM_IDENTICAL_CONSECUTIVE_CHARS = 2;
const string CAPTAL_LETTERS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const string NUMBERS = "0123456789";
//random possible character pool
List <string> CHARACTER_ARRAY = new List <string> {
CAPTAL_LETTERS, NUMBERS
};
//character pool to generate raw password.
string characterSet = "";
System.Random random = new System.Random();
//raw password holder
char[] password = new char[6];
for (int characterPosition = 0; characterPosition < 6; characterPosition++)
{
password[characterPosition] = characterSet[random.Next(characterSet.Length - 1)];
bool moreThanTwoIdenticalInARow =
characterPosition >= MAXIMUM_IDENTICAL_CONSECUTIVE_CHARS &&
password[characterPosition] == password[characterPosition - 1] &&
password[characterPosition - 1] == password[characterPosition - 2];
if (moreThanTwoIdenticalInARow)
{
characterPosition--;
}
}
//check if 6 random characters are 2 different types
int CAPITAL_LETTER_COUNT = 0;
int NUMBER_COUNT = 0;
//Count each type
for (int i = 0; i < password.Length; i++)
{
if (CAPTAL_LETTERS.Contains(password[i].ToString()))
{
CAPITAL_LETTER_COUNT++;
}
else if (NUMBERS.Contains(password[i].ToString()))
{
NUMBER_COUNT++;
}
}
List <string> LEFT_RANDOM = new List <string>();
if (CAPITAL_LETTER_COUNT == 0)
{
LEFT_RANDOM.Add(CAPTAL_LETTERS);
}
if (NUMBER_COUNT == 0)
{
LEFT_RANDOM.Add(NUMBERS);
}
string str_password = string.Join(null, password);
if (LEFT_RANDOM.Count > 1)
{
//get random Character set wheren count = 0
string leftcharSet = LEFT_RANDOM[random.Next(LEFT_RANDOM.Count - 1)];
//replace last character with another random character
str_password = str_password.Remove(7, 1) + random.Next(leftcharSet.Length - 1).ToString();
}
return(str_password);
}