class Program
{
//创建Task任务的三种方式（无返回值）
static void Main(string[] args)
{
//方法一
Task task1 = new Task(() =>
{
Console.WriteLine("方法一异步任务");
Thread.Sleep(2000);
});
task1.Start();
Task.WaitAll(task1);
//方法二
Task.Run(() =>
{
Console.WriteLine("方法二异步任务");
});
//方法三
Task.Factory.StartNew(() =>
{
Console.WriteLine("方法三：通过工厂创建异步任务对象");
});
Console.ReadLine();
}
}
//创建Task任务的三种方式（无返回值）
static void Main(string[] args)
{
var t1 = new Task(() => TaskMethod("task1"));
var t2 = new Task(() => TaskMethod("task2"));
t1.Start();
t2.Start();
Task.WaitAll(t1, t2);
Task.Run(() => TaskMethod("task3"));
Task.Factory.StartNew(() => TaskMethod("task4"));
Task.Factory.StartNew(() => TaskMethod("task5"), TaskCreationOptions.LongRunning);
Console.WriteLine("主线程开始执行任务");
Task task = new Task(() =>
{
Console.WriteLine("使用System.Threading.Tasks.Task执行异步操作.");
for (int i = 0; i < 10; i++)
{
Console.WriteLine(i);
}
});
task.Start();
Console.WriteLine("主线程执行其他任务");
task.Wait();
Console.ReadLine();
}
static void TaskMethod(string taskName)
{
Console.WriteLine($"任务名称：{taskName}，线程Id：{Thread.CurrentThread.ManagedThreadId},是否为线程池执行：{Thread.CurrentThread.IsThreadPoolThread}");
}
/// <summary>
/// 带返回值的Task<int>案例代码
/// </summary>
/// <param name="args"></param>
static void Main(string[] args)
{
TaskMethod("main task");
Task<int> task = CreateTask("task1");
task.Start();
int result = task.Result;
Console.WriteLine("task1 result is :" + result);
task =CreateTask("task2");
task.RunSynchronously();//在当前主线程中同步执行task
result = task.Result;
Console.WriteLine("task2 result is :" + result);
task = CreateTask("task3");
Console.WriteLine(task.Status);
task.Start();
while (!task.IsCompleted)
{
Console.WriteLine(task.Status);
Thread.Sleep(1000);
}
//常规使用方法
task = new Task<int>(() => Getsum());
task.Start();
Console.WriteLine("主线程执行其他任务");
task.Wait();
Console.WriteLine("获取task执行结果" + task.Result.ToString());
Console.ReadLine();
}
static Task<int> CreateTask(string name)
{
return new Task<int>(() => TaskMethod(name));
}
static int TaskMethod(string name)
{
Console.WriteLine("Task {0} is running on a thread id {1}. Is thread pool thread: {2}",
name, Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.IsThreadPoolThread);
Thread.Sleep(TimeSpan.FromSeconds(2));
return 42;
}
static int Getsum()
{
int sum = 0;
Console.WriteLine("使用Task执行异步操作.");
for (int i = 0; i < 100; i++)
{
sum += i;
}
return sum;
}
/// <summary>
/// async/await实现带返回值task
/// </summary>
/// <param name="args"></param>
static void Main(string[] args)
{
Task<int> task = AsyncMethod();
Console.WriteLine("主线程执行其他处理,线程id:"+Thread.CurrentThread.ManagedThreadId);
for (int i = 1; i <= 3; i++)
Console.WriteLine("Call Main()");
int result = task.Result;//阻塞主线程
Console.WriteLine("任务执行结果：{0}", result);
Console.ReadLine();
}
async static Task<int> AsyncMethod()
{
Console.WriteLine("使用Task执行异步操作.线程id:" + Thread.CurrentThread.ManagedThreadId);
await Task.Delay(1000);
int sum = 0;
Console.WriteLine("使用Task执行异步操作.线程id:"+Thread.CurrentThread.ManagedThreadId);
for (int i = 0; i < 100; i++)
{
sum += i;
}
return sum;
}
/// <summary>
/// 并行任务
/// </summary>
/// <param name="args"></param>
static void Main(string[] args)
{
ConcurrentStack<int> stack = new ConcurrentStack<int>();
var t1 = new Task(() =>
{
stack.Push(1);
stack.Push(2);
});
t1.Start();
Console.WriteLine(DateTime.Now.ToString());
//t2 t3并行执行
var t2 = t1.ContinueWith((task) =>
{
int result;
stack.TryPop(out result);
Console.WriteLine("Task t2 pop result={0},Thread id {1}", result, Thread.CurrentThread.ManagedThreadId);
});
//t2,t3并行执行
var t3 = t1.ContinueWith(t =>
{
int result;
stack.TryPop(out result);
Console.WriteLine("Task t3 pop result={0},Thread id {1}", result, Thread.CurrentThread.ManagedThreadId);
});
Task.WaitAll(t2, t3);
//t4串行执行
var t4 = Task.Factory.StartNew(() =>
{
Console.WriteLine("当前集合元素个数：{0},Thread id {1}", stack.Count, Thread.CurrentThread.ManagedThreadId);
});
t4.Wait();
Console.ReadLine();
}
/// <summary>
/// 子任务
/// </summary>
/// <param name="args"></param>
static void Main(string[] args)
{
Task<string[]> parent = new Task<string[]>(() =>
{
string[] array = new string[2];
new Task(() => { array[0] = "result1";Thread.Sleep(2000); }, TaskCreationOptions.AttachedToParent).Start();
new Task(() => { array[1] = "result2"; Thread.Sleep(2000); }, TaskCreationOptions.AttachedToParent).Start();
return array;
});
parent.ContinueWith((task) =>
{
foreach(string str in task.Result)
{
Console.WriteLine("结果：" + str);
}
});
parent.Start();
Console.WriteLine("主线程");
parent.Wait();//wait只能等到父Task结束，不能等到父线程的ContinueWith结束
Console.WriteLine("主线程");
Console.ReadLine();
}
/// <summary>
/// 取消任务
/// </summary>
/// <param name="args"></param>
static void Main(string[] args)
{
var cts = new CancellationTokenSource();
var task = new Task<int>(() => TaskMethod("task 1", 10, cts.Token), cts.Token);
Console.WriteLine(task.Status);
Console.ReadLine();
cts.Cancel();
Console.WriteLine(task.Status);
Console.WriteLine("task1已经被取消！");
cts = new CancellationTokenSource();
task = new Task<int>(() => TaskMethod("task2 ", 10, cts.Token), cts.Token);
task.Start();
for (int i = 0; i < 10; i++)
{
Thread.Sleep(500);
Console.WriteLine(task.Status);
}
cts.Cancel();
for (int i = 0; i < 5; i++)
{
Thread.Sleep(500);
Console.WriteLine(task.Status);
}
Console.ReadLine();
}
static int TaskMethod(string name, int seconds, CancellationToken token)
{
Console.WriteLine("Task {0} is running on a thread id {1}. Is thread pool thread: {2}",
name, Thread.CurrentThread.ManagedThreadId, Thread.CurrentThread.IsThreadPoolThread);
for(int i = 0; i < seconds; i++)
{
Thread.Sleep(500);
if (token.IsCancellationRequested)
{
return -1;
}
}
return 42 * seconds;
}