TaskContinueWith.cs

using System;
using System.Threading.Tasks;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            TaskScheduler.UnobservedTaskException += (sender, e) =>
            {
                Console.WriteLine(e.Exception.ToString());
            };

            // var task1 = Task.Run(() => throw new Exception());
            // var task2 = task1.ContinueWith
            // と書くと、 task1 が GC されないので UnobservedTaskException が発生しない

            var task = Task.Run(() => throw new Exception())
                .ContinueWith(t => Console.WriteLine("hoge"));
            task.Wait();
            Console.WriteLine(task.Status);

            GC.Collect();
            GC.WaitForPendingFinalizers();
        }
    }
}