यहाँ एक उदाहरण है कि में दो अंक दर्शाता है जवाब से मैक्स Galkin :
class Program
{
static void Main(string[] args)
{
Console.WriteLine("*********************************************************************");
Console.WriteLine("* Start canceled task, don't pass token to constructor");
Console.WriteLine("*********************************************************************");
StartCanceledTaskTest(false);
Console.WriteLine();
Console.WriteLine("*********************************************************************");
Console.WriteLine("* Start canceled task, pass token to constructor");
Console.WriteLine("*********************************************************************");
StartCanceledTaskTest(true);
Console.WriteLine();
Console.WriteLine("*********************************************************************");
Console.WriteLine("* Throw if cancellation requested, don't pass token to constructor");
Console.WriteLine("*********************************************************************");
ThrowIfCancellationRequestedTest(false);
Console.WriteLine();
Console.WriteLine("*********************************************************************");
Console.WriteLine("* Throw if cancellation requested, pass token to constructor");
Console.WriteLine("*********************************************************************");
ThrowIfCancellationRequestedTest(true);
Console.WriteLine();
Console.WriteLine();
Console.WriteLine("Test Done!!!");
Console.ReadKey();
}
static void StartCanceledTaskTest(bool passTokenToConstructor)
{
Console.WriteLine("Creating task");
CancellationTokenSource tokenSource = new CancellationTokenSource();
Task task = null;
if (passTokenToConstructor)
{
task = new Task(() => TaskWork(tokenSource.Token, false), tokenSource.Token);
}
else
{
task = new Task(() => TaskWork(tokenSource.Token, false));
}
Console.WriteLine("Canceling task");
tokenSource.Cancel();
try
{
Console.WriteLine("Starting task");
task.Start();
task.Wait();
}
catch (Exception ex)
{
Console.WriteLine("Exception: {0}", ex.Message);
if (ex.InnerException != null)
{
Console.WriteLine("InnerException: {0}", ex.InnerException.Message);
}
}
Console.WriteLine("Task.Status: {0}", task.Status);
}
static void ThrowIfCancellationRequestedTest(bool passTokenToConstructor)
{
Console.WriteLine("Creating task");
CancellationTokenSource tokenSource = new CancellationTokenSource();
Task task = null;
if (passTokenToConstructor)
{
task = new Task(() => TaskWork(tokenSource.Token, true), tokenSource.Token);
}
else
{
task = new Task(() => TaskWork(tokenSource.Token, true));
}
try
{
Console.WriteLine("Starting task");
task.Start();
Thread.Sleep(100);
Console.WriteLine("Canceling task");
tokenSource.Cancel();
task.Wait();
}
catch (Exception ex)
{
Console.WriteLine("Exception: {0}", ex.Message);
if (ex.InnerException != null)
{
Console.WriteLine("InnerException: {0}", ex.InnerException.Message);
}
}
Console.WriteLine("Task.Status: {0}", task.Status);
}
static void TaskWork(CancellationToken token, bool throwException)
{
int loopCount = 0;
while (true)
{
loopCount++;
Console.WriteLine("Task: loop count {0}", loopCount);
token.WaitHandle.WaitOne(50);
if (token.IsCancellationRequested)
{
Console.WriteLine("Task: cancellation requested");
if (throwException)
{
token.ThrowIfCancellationRequested();
}
break;
}
}
}
}
आउटपुट:
*********************************************************************
* Start canceled task, don't pass token to constructor
*********************************************************************
Creating task
Canceling task
Starting task
Task: loop count 1
Task: cancellation requested
Task.Status: RanToCompletion
*********************************************************************
* Start canceled task, pass token to constructor
*********************************************************************
Creating task
Canceling task
Starting task
Exception: Start may not be called on a task that has completed.
Task.Status: Canceled
*********************************************************************
* Throw if cancellation requested, don't pass token to constructor
*********************************************************************
Creating task
Starting task
Task: loop count 1
Task: loop count 2
Canceling task
Task: cancellation requested
Exception: One or more errors occurred.
InnerException: The operation was canceled.
Task.Status: Faulted
*********************************************************************
* Throw if cancellation requested, pass token to constructor
*********************************************************************
Creating task
Starting task
Task: loop count 1
Task: loop count 2
Canceling task
Task: cancellation requested
Exception: One or more errors occurred.
InnerException: A task was canceled.
Task.Status: Canceled
Test Done!!!