Example of handling exceptions in a task list.

test.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace TestListAsyncAndExceptions
{
    class Program
    {
        static void Main(string[] args)
        {
            using (System.CodeDom.Compiler.IndentedTextWriter writer = new System.CodeDom.Compiler.IndentedTextWriter(Console.Out, "    "))
            {
                Console.SetOut(writer);

                var taskList = new List<Task> {
                                   GoodTask(100,"A"),
                                   GoodTask(300,"B"),
                                   GoodTask(200,"C"),
                                   BadTask(500,"D"),
                                   GoodTask(400,"E"),
                                   BadTask(600,"F",new Exception("Generic Exception")),
                                   GoodTask(900,"G"),
                                   BadTask(800,"H",new DivideByZeroException("Woot, 1/0 blew it up")),
                                   GoodTask(700,"I"),
                               };
                Console.WriteLine("Start Waiting");
                try
                {
                    Task.WaitAll(taskList.ToArray());
                }
                catch (Exception myException)
                {
                    Console.WriteLine(myException.Message);
                    foreach (var innerException in taskList.Where(x=>x.IsFaulted))
                    {
                        writer.Indent = 1;
                        Console.WriteLine(innerException.Exception.InnerException.Message);
                        writer.Indent = 0;
                    }
                }
                Console.WriteLine("Done Waiting");
            }
            Console.ReadLine();
        }

        public static async Task GoodTask(int delayTime, string name)
        {
            await Task.Delay(delayTime);
            Console.WriteLine(name);
        }

        public static async Task BadTask(int delayTime, string name)
        {
            await BadTask(delayTime, name, new Exception("You left the exceptionToThrow argument of BadTask empty"));
        }

        public static async Task BadTask(int delayTime, string name, Exception exceptionToThrow)
        {
            await Task.Delay(delayTime);
            Console.WriteLine(name);
            throw exceptionToThrow;
        }

    }
}