.NET Short Unique Identifier

Question

I need a unique identifier in .NET (cannot use GUID as it is too long for this case).

Do people think that the algorithm used here is a good candidate or do you have

Answer 1

Here's my small method to generate a random and short unique id. Uses a cryptographic rng for secure random number generation. Add whatever characters you need to the chars string.

private string GenerateRandomId(int length)
{
    char[] stringChars = new char[length];
    byte[] randomBytes = new byte[length];
    using (RandomNumberGenerator rng = RandomNumberGenerator.Create())
    {
        rng.GetBytes(randomBytes);
    }

    string chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";           

    for (int i = 0; i < stringChars.Length; i++)
    {
        stringChars[i] = chars[randomBytes[i] % chars.Length];
    }

    return new string(stringChars);
}