C# 5.0 Task中实现异常抛出

using System;
using System.Threading;
using System.Threading.Tasks;

namespace ExceptionsDemo
{
class Program
{
static void Main(string[] args)
{
Task<int> task;
try
{
task = Task.Run(() => TaskMethod("task 1", 2));
//Thread.Sleep(TimeSpan.FromSeconds(3));
//task.Wait();
int result = task.Result;
Console.WriteLine("result: {0}", result);
}
catch (Exception ex)
{
Console.WriteLine("exception caught: {0}", ex);
}

Console.WriteLine("------------------------------");
Console.WriteLine();

try
{
task = Task.Run(() => TaskMethod("task 2", 2));
//用此种方式来获取任务的返回值，如果有的话
int result = task.GetAwaiter().GetResult();
Console.WriteLine("result: {0}", result);
}
catch (Exception ex)
{
//异常信息将与task1中不同
Console.WriteLine("exception caught: {0}", ex);
}

Console.WriteLine("------------------------------");
Console.WriteLine();

var t1 = new Task<int>(() => TaskMethod("task 3", 3));
var t2 = new Task<int>(() => TaskMethod("task 4", 2));
var complexTask = Task.WhenAll(t1, t2);
var exceptionHandler = complexTask.ContinueWith(t =>
Console.WriteLine("exception caught: {0}", t.Exception),
//仅当任务失败时才做的事
TaskContinuationOptions.OnlyOnFaulted);

t1.Start();
t2.Start();

Console.ReadKey();
}

static int TaskMethod(string name, int seconds)
{
Console.WriteLine("Task {0} is running on a thread is {1}. is thread pool thread {2}",
name,
Thread.CurrentThread.ManagedThreadId,
Thread.CurrentThread.IsThreadPoolThread);
Thread.Sleep(TimeSpan.FromSeconds(seconds));
//出现运行异常时
//尝试修改 ‘工具’‘选项’‘调试’‘常规’将【启用仅我的代码】去除勾选
throw new Exception("Boom!");
return 42 * seconds;
}
}
}