Advanced C#

Topics:
Higher Calling Functions
Lazy Code
Asynch and Parallel

static void Main(string[] args)
{
 var elapsed = Measure(() =>
 {
  var numbers = new[]{3, 5, 7, 9, 11, 13};
  foreach(var prime in numbers.Find(IsPrime).Take(2))
  {
   Console.WriteLine(prime);
  }
 });
 Console.WriteLine(elapsed);

 //Parallel
 Parallel.Invoke(new Action[]
 {
  () => FindLargePrimes(3,100),
  () => FindLargePrimes(101,200)
 });

 //Task
 var task = new Task<IEnumerable<int>>(
  () => FindLargePrimes(3,100)
 );
 var task2 = task.ContinueWith((antecedent) =>
      {
       foreach(var number in antecedent.Result)
       {
        Console.WriteLine(number);
       }
      });
 task.Start();
 Console.WriteLine("Doing other work");
 task2.Wait();
}

private static IEnumerable<int> Find(this IEnumerable<int> values, Func<int, bool> test)
{
 foreach(var number in values)
 {
  if(test(number))
  {
   yield return number;
  }
 }
}

private static bool IsPrime(int number) [...]

private TimeSpan Measure(Action action)
{
 var watch = new StopWatch();
 watch.start();
 action();
 return watch.Elapsed;
}

Reference: Scott Allen's C# Fundamentals - Part 2