Question

Is it possible to create a random number from a selection of numbers in c#.

For example I have an array of numbers from 1-90 and once a number has been called a propery of that number changes. I therefore only want to generate the numbers where that property has not changed.
This will therefore only randomly call the numbers between 1 and 90 one.

I have done this using a loop but just wanted a quiker and cleaner method if possible.

My current code is:

    public object GenerateNumber()
    {
        bool alreadyCalled = false;
        while (!alreadyCalled)
        {
           Random randomNumber = new Random(System.DateTime.Now.Millisecond);
            int RandomNumberCalled = randomNumber.Next(1, 91);             


            if (Numbers.ToList().Find(x => x.Number == RandomNumberCalled).IsCalled != null)
            {    

             // change number to is called and do other things. 

            }
        }
        return false;
    }

Answer 1

list<int> myNumbers=GetNumbers();
Random r=new Random();
while (myNumbers.Count()>0)
{
  int index=r.Next(myNumbers.Count());
  ReportSelectedNumber(myNumbers[index]);
  myNumbers.RemoveAt(index);
}

Make sure that you have GetNumbers() that will return you the list you want your numbers to be selected from, and ReportSelectedNumber() for doing something with recently selected number.