[Jumpstart C#] loops demo - Foreach

using System;
using System.Collections.Generic;

#region Primes class
public class Primes : IEnumerable<uint>
{
    private uint val = 1;

    public IEnumerator<uint> GetEnumerator()
    {
        bool isPrime;
        uint maxDivider;
        while (true)
        {
            isPrime = true;
            maxDivider = (uint)Math.Sqrt(val);
            for (int i = 2; i <= maxDivider; i++)
            {
                if (val % i == 0)
                {
                    isPrime = false;
                    break;
                }
            }

            val++;

            if (isPrime)
                yield return val - 1;
        }
    }

    System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
    {
        return GetEnumerator();
    }

}
#endregion

class ForEachExample
{
    static void Main()
    {
        //// An array of integers
        //int[] numbers = { 10, 32, 3, 54, 15 };

        //foreach (int n in numbers)
        //{
        //    Console.WriteLine(n);
        //}


        //// An array of strings
        //string[] days = { "Monday", "Tuesday", "Wednesday", "Thursday", "Friday" };

        //foreach (string day in days)
        //{
        //    Console.WriteLine(day);
        //}

        //endless loop
        Primes primes = new Primes();

        foreach (uint prime in primes)
        {
            Console.WriteLine(prime);
        }
    }
}