using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.Linq;

using System.Text;

using System.Threading;

using System.Threading.Tasks;

namespace AsyncExampleNET45

{

class Program

{

static readonly TimeSpan WaitTime = TimeSpan.FromSeconds(20);

static async Task Main(string[] args)

{

var listener = new TextWriterTraceListener(Console.Out);

Trace.Listeners.Add(listener);

using (var TokenSource = new CancellationTokenSource())

using (ConsoleUtils.SetConsoleCtrl.Create(type => {

TokenSource?.Cancel();

return false;

}))

await MainAction(TokenSource.Token);

}

static async Task MainAction(CancellationToken Token)

{

DateTime StartTime = DateTime.Now;

await Task.Factory.StartNew(() => Task2Action(StartTime, Token)).Unwrap();

Trace.WriteLine($"Task1 {DateTime.Now - StartTime}");

await Task.Run(() => Task4Action(StartTime, Token));

Trace.WriteLine($"Task3 {DateTime.Now - StartTime}");

}

static async Task Task2Action(DateTime StartTime, CancellationToken Token)

{

await Task.Delay(WaitTime, Token);

Trace.WriteLine($"Task2 {DateTime.Now - StartTime}");

}

static async Task Task4Action(DateTime StartTime, CancellationToken Token)

{

await Task.Delay(WaitTime, Token);

Trace.WriteLine($"Task4 {DateTime.Now - StartTime}");

}

}

}