здесь мое решение, небезопасно для параллелизма, не более 1000 GUID в секунду и потокобезопасен.
public static class Extensors
{
private static object _lockGuidObject;
public static string GetGuid()
{
if (_lockGuidObject == null)
_lockGuidObject = new object();
lock (_lockGuidObject)
{
Thread.Sleep(1);
var epoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
var epochLong = Convert.ToInt64((DateTime.UtcNow - epoch).TotalMilliseconds);
return epochLong.DecimalToArbitrarySystem(36);
}
}
/// <summary>
/// Converts the given decimal number to the numeral system with the
/// specified radix (in the range [2, 36]).
/// </summary>
/// <param name="decimalNumber">The number to convert.</param>
/// <param name="radix">The radix of the destination numeral system (in the range [2, 36]).</param>
/// <returns></returns>
public static string DecimalToArbitrarySystem(this long decimalNumber, int radix)
{
const int BitsInLong = 64;
const string Digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
if (radix < 2 || radix > Digits.Length)
throw new ArgumentException("The radix must be >= 2 and <= " + Digits.Length.ToString());
if (decimalNumber == 0)
return "0";
int index = BitsInLong - 1;
long currentNumber = Math.Abs(decimalNumber);
char[] charArray = new char[BitsInLong];
while (currentNumber != 0)
{
int remainder = (int)(currentNumber % radix);
charArray[index--] = Digits[remainder];
currentNumber = currentNumber / radix;
}
string result = new String(charArray, index + 1, BitsInLong - index - 1);
if (decimalNumber < 0)
{
result = "-" + result;
}
return result;
}
код не оптимизирован, просто пример!.