using System;

using System.Threading.Tasks;

using System.Threading;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine(SynchronizationContext.Current == null);

        new Program().DoSomething().Wait();

    }

​

    public async Task DoSomething()

    {

        Console.WriteLine("Starting thread: " + Thread.CurrentThread.ManagedThreadId);

        var listofProcessor = new List<Processor>{new Processor("Processor"), new Processor("Processor1")};

        try

        {

            var tasks = listofProcessor.Select(x => x.Process());

            Console.WriteLine("Before Task.WhenAll  " + Thread.CurrentThread.ManagedThreadId);

            await Task.WhenAll(tasks);

            Console.WriteLine("After Task.WhenAll " + Thread.CurrentThread.ManagedThreadId);

        }

        catch (Exception e)

        {

            Console.WriteLine("Exception caught");

        }

    }

​

    public class Processor

    {

        private string _name;

        public Processor(string name)

        {

            _name = name;

        }

​

        public async Task<string> Process()

        {

            Console.WriteLine(_name + " BeforeAwait " + Thread.CurrentThread.ManagedThreadId);

            await Task.Delay(100);

            Console.WriteLine(_name + " AfterAwait " + Thread.CurrentThread.ManagedThreadId);

            return "hellow";

        }

    }

}