Question

Currently my program (see below) generates random strings (made of numbers) from 8 – 12 characters in length.

public static string GenerateNewCode(int CodeLength)
{
    string newCode = String.Empty;
    int seed = unchecked(DateTime.Now.Ticks.GetHashCode());
    Random random = new Random(seed);

    // keep going until we find a unique code       `
    do
    {
        newCode = random.Next(Convert.ToInt32(Math.Pow(10, CodeLength - 1)), Convert.ToInt32(Math.Pow(10, CodeLength) - 1)).ToString("0000");
    }
    while (!ConsumerCode.isUnique(newCode));

    // return
    return newCode;
}

However, their is a problem with the method, when the codeLength is 10 or greater it causes error because 10⁹ is greater than int32.MaxValue.

Not sure how to get around this issue.

Answer 1

Your code doing the same thing without some freak lines:

public static string GenerateNewCode(int CodeLength)
{
    Random random = new Random();
    StringBuilder output = new StringBuilder();

    do
    {   
        for (int i = 0; i < CodeLength; i++)
        {
            output.Append(random.Next(0, 10));
        }
    }
    while (!ConsumerCode.isUnique(output.ToString()));
    return output.ToString();
}