本文整理汇总了C#中System.Threading.Tasks.Task类的典型用法代码示例。如果您正苦于以下问题：C# Task类的具体用法？C# Task怎么用？C# Task使用的例子？那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。
Task类属于System.Threading.Tasks命名空间，在下文中一共展示了Task类的8个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: Main
//引入命名空间
using System;
using System.Threading;
using System.Threading.Tasks;
class Example
{
static void Main()
{
Action<object> action = (object obj) =>
{
Console.WriteLine("Task={0}, obj={1}, Thread={2}",
Task.CurrentId, obj,
Thread.CurrentThread.ManagedThreadId);
};
// Create a task but do not start it.
Task t1 = new Task(action, "alpha");
// Construct a started task
Task t2 = Task.Factory.StartNew(action, "beta");
// Block the main thread to demonstrate that t2 is executing
t2.Wait();
// Launch t1
t1.Start();
Console.WriteLine("t1 has been launched. (Main Thread={0})",
Thread.CurrentThread.ManagedThreadId);
// Wait for the task to finish.
t1.Wait();
// Construct a started task using Task.Run.
String taskData = "delta";
Task t3 = Task.Run( () => {Console.WriteLine("Task={0}, obj={1}, Thread={2}",
Task.CurrentId, taskData,
Thread.CurrentThread.ManagedThreadId);
});
// Wait for the task to finish.
t3.Wait();
// Construct an unstarted task
Task t4 = new Task(action, "gamma");
// Run it synchronously
t4.RunSynchronously();
// Although the task was run synchronously, it is a good practice
// to wait for it in the event exceptions were thrown by the task.
t4.Wait();
}
}输出：
Task=1, obj=beta, Thread=3 t1 has been launched. (Main Thread=1) Task=2, obj=alpha, Thread=4 Task=3, obj=delta, Thread=3 Task=4, obj=gamma, Thread=1
示例2: Main
//引入命名空间
using System;
using System.Threading.Tasks;
public class Example
{
public static async Task Main()
{
await Task.Run( () => {
// Just loop.
int ctr = 0;
for (ctr = 0; ctr <= 1000000; ctr++)
{}
Console.WriteLine("Finished {0} loop iterations",
ctr);
} );
}
}输出：
Finished 1000001 loop iterations
示例3: Main
//引入命名空间
using System;
using System.Threading.Tasks;
public class Example
{
public static void Main()
{
Task t = Task.Factory.StartNew( () => {
// Just loop.
int ctr = 0;
for (ctr = 0; ctr <= 1000000; ctr++)
{}
Console.WriteLine("Finished {0} loop iterations",
ctr);
} );
t.Wait();
}
}输出：
Finished 1000001 loop iterations
示例4: Random
//引入命名空间
using System;
using System.Threading;
using System.Threading.Tasks;
class Program
{
static Random rand = new Random();
static void Main()
{
// Wait on a single task with no timeout specified.
Task taskA = Task.Run( () => Thread.Sleep(2000));
Console.WriteLine("taskA Status: {0}", taskA.Status);
try {
taskA.Wait();
Console.WriteLine("taskA Status: {0}", taskA.Status);
}
catch (AggregateException) {
Console.WriteLine("Exception in taskA.");
}
}
}输出：
taskA Status: WaitingToRun taskA Status: RanToCompletion
示例5: Main
//引入命名空间
using System;
using System.Threading;
using System.Threading.Tasks;
public class Example
{
public static void Main()
{
// Wait on a single task with a timeout specified.
Task taskA = Task.Run( () => Thread.Sleep(2000));
try {
taskA.Wait(1000); // Wait for 1 second.
bool completed = taskA.IsCompleted;
Console.WriteLine("Task A completed: {0}, Status: {1}",
completed, taskA.Status);
if (! completed)
Console.WriteLine("Timed out before task A completed.");
}
catch (AggregateException) {
Console.WriteLine("Exception in taskA.");
}
}
}输出：
Task A completed: False, Status: Running Timed out before task A completed.
示例6: Main
//引入命名空间
using System;
using System.Threading;
using System.Threading.Tasks;
public class Example
{
public static void Main()
{
var tasks = new Task[3];
var rnd = new Random();
for (int ctr = 0; ctr <= 2; ctr++)
tasks[ctr] = Task.Run( () => Thread.Sleep(rnd.Next(500, 3000)));
try {
int index = Task.WaitAny(tasks);
Console.WriteLine("Task #{0} completed first.\n", tasks[index].Id);
Console.WriteLine("Status of all tasks:");
foreach (var t in tasks)
Console.WriteLine(" Task #{0}: {1}", t.Id, t.Status);
}
catch (AggregateException) {
Console.WriteLine("An exception occurred.");
}
}
}输出：
Task #1 completed first. Status of all tasks: Task #3: Running Task #1: RanToCompletion Task #4: Running
示例7: Main
//引入命名空间
using System;
using System.Threading;
using System.Threading.Tasks;
public class Example
{
public static void Main()
{
// Wait for all tasks to complete.
Task[] tasks = new Task[10];
for (int i = 0; i < 10; i++)
{
tasks[i] = Task.Run(() => Thread.Sleep(2000));
}
try {
Task.WaitAll(tasks);
}
catch (AggregateException ae) {
Console.WriteLine("One or more exceptions occurred: ");
foreach (var ex in ae.Flatten().InnerExceptions)
Console.WriteLine(" {0}", ex.Message);
}
Console.WriteLine("Status of completed tasks:");
foreach (var t in tasks)
Console.WriteLine(" Task #{0}: {1}", t.Id, t.Status);
}
}输出：
Status of completed tasks: Task #2: RanToCompletion Task #1: RanToCompletion Task #3: RanToCompletion Task #4: RanToCompletion Task #6: RanToCompletion Task #5: RanToCompletion Task #7: RanToCompletion Task #8: RanToCompletion Task #9: RanToCompletion Task #10: RanToCompletion
示例8: Main
//引入命名空间
using System;
using System.Threading;
using System.Threading.Tasks;
public class Example
{
public static void Main()
{
// Create a cancellation token and cancel it.
var source1 = new CancellationTokenSource();
var token1 = source1.Token;
source1.Cancel();
// Create a cancellation token for later cancellation.
var source2 = new CancellationTokenSource();
var token2 = source2.Token;
// Create a series of tasks that will complete, be cancelled,
// timeout, or throw an exception.
Task[] tasks = new Task[12];
for (int i = 0; i < 12; i++)
{
switch (i % 4)
{
// Task should run to completion.
case 0:
tasks[i] = Task.Run(() => Thread.Sleep(2000));
break;
// Task should be set to canceled state.
case 1:
tasks[i] = Task.Run( () => Thread.Sleep(2000),
token1);
break;
case 2:
// Task should throw an exception.
tasks[i] = Task.Run( () => { throw new NotSupportedException(); } );
break;
case 3:
// Task should examine cancellation token.
tasks[i] = Task.Run( () => { Thread.Sleep(2000);
if (token2.IsCancellationRequested)
token2.ThrowIfCancellationRequested();
Thread.Sleep(500); }, token2);
break;
}
}
Thread.Sleep(250);
source2.Cancel();
try {
Task.WaitAll(tasks);
}
catch (AggregateException ae) {
Console.WriteLine("One or more exceptions occurred:");
foreach (var ex in ae.InnerExceptions)
Console.WriteLine(" {0}: {1}", ex.GetType().Name, ex.Message);
}
Console.WriteLine("\nStatus of tasks:");
foreach (var t in tasks) {
Console.WriteLine(" Task #{0}: {1}", t.Id, t.Status);
if (t.Exception != null) {
foreach (var ex in t.Exception.InnerExceptions)
Console.WriteLine(" {0}: {1}", ex.GetType().Name,
ex.Message);
}
}
}
}输出：
One or more exceptions occurred: TaskCanceledException: A task was canceled. NotSupportedException: Specified method is not supported. TaskCanceledException: A task was canceled. TaskCanceledException: A task was canceled. NotSupportedException: Specified method is not supported. TaskCanceledException: A task was canceled. TaskCanceledException: A task was canceled. NotSupportedException: Specified method is not supported. TaskCanceledException: A task was canceled. Status of tasks: Task #13: RanToCompletion Task #1: Canceled Task #3: Faulted NotSupportedException: Specified method is not supported. Task #8: Canceled Task #14: RanToCompletion Task #4: Canceled Task #6: Faulted NotSupportedException: Specified method is not supported. Task #7: Canceled Task #15: RanToCompletion Task #9: Canceled Task #11: Faulted NotSupportedException: Specified method is not supported. Task #12: Canceled