Hi, I am using .NET to create an artificial life program and I am using C#'s pseudo random class defined in a Singleton. The idea is that if I use the same random number generator throughout the application, I could merely save the seed and then reload from the seed to recompute a certain interesting run.

public sealed class RandomNumberGenerator : Random
{
    private static readonly RandomNumberGenerator instance = new RandomNumberGenerator();

    RandomNumberGenerator()
    {

    }

    public static RandomNumberGenerator Instance
    {
        get
        {
            return instance;
        }
    }
}

I also wanted a method that could give me two different random numbers.

public static Tuple<int, int> TwoDifferentRandomNumbers(this Random rnd, int minValue, int maxValue)
    {
        if (minValue >= maxValue)
            throw new ArgumentOutOfRangeException("maxValue", "maxValue must be greater than minValue");
        if (minValue + 1 == maxValue)
            return Tuple.Create<int, int>(minValue, maxValue);

        int rnd1 = rnd.Next(minValue, maxValue);
        int rnd2 = rnd.Next(minValue, maxValue);
        while (rnd1 == rnd2)
        {                
            rnd2 = rnd.Next(minValue, maxValue);
        }
        return Tuple.Create<int, int>(rnd1, rnd2);            
    }

The problem is that sometimes rnd.Next(minValue,maxValuealways returns minValue. If I breakpoint at this point and try creating a double and setting it to rnd.NextDouble(), it returns 0.0. Anyone know why this is happening?

I know that it is a pseudo random number generator, but frankly, I hadn't expected it to lock at 0. The random number generator is being accessed from multiple threads... could this be the source of the problem?