public void CancelDelayedTest()
{
// prepare
var syncContext = new SynchronizationContext();
var anotherSyncContext = new SynchronizationContext();
var stopWatch = new Stopwatch().Also((it) => it.Start());
// cancel before execution
var executed = false;
var token = syncContext.PostDelayed(() =>
{
executed = true;
}, 500);
Thread.Sleep(200);
Assert.IsTrue(syncContext.CancelDelayed(token), "Call-back cancellation should be successful.");
Thread.Sleep(500);
Assert.IsFalse(executed, "Call-back should not be executed after cancellation.");
Assert.IsFalse(syncContext.CancelDelayed(token), "Call-back cancellation should be failed.");
// cancel after execution
executed = false;
token = syncContext.PostDelayed(() =>
{
executed = true;
}, 200);
Thread.Sleep(500);
Assert.IsTrue(executed, "Call-back should be executed.");
Assert.IsFalse(syncContext.CancelDelayed(token), "Call-back cancellation should be failed after execution.");
// cancel by another synchronization context
executed = false;
token = syncContext.PostDelayed(() =>
{
executed = true;
}, 200);
Assert.IsFalse(anotherSyncContext.CancelDelayed(token), "Call-back cancellation should be failed by another synchronization context.");
Thread.Sleep(500);
Assert.IsTrue(executed, "Call-back should be executed.");
}
public void PostDelayedTest()
{
// prepare
var syncContext = new SynchronizationContext();
var stopWatch = new Stopwatch().Also((it) => it.Start());
// post without delay time
var syncLock = new object();
var postTime = stopWatch.ElapsedMilliseconds;
var executionTime = 0L;
lock (syncLock)
{
syncContext.PostDelayed(() =>
{
executionTime = stopWatch.ElapsedMilliseconds;
lock (syncLock)
{
Monitor.Pulse(syncLock);
}
}, 0);
Assert.IsTrue(Monitor.Wait(syncLock, 1000), "Posted call-back not executed.");
Assert.GreaterOrEqual(executionTime - postTime, 0, "Call-back executed too early.");
Assert.LessOrEqual(executionTime - postTime, 200, "Call-back executed too late.");
}
// post with delayed time on multi-threads
var completedCount = 0;
var exception = (Exception?)null;
lock (syncLock)
{
for (var i = 0; i < 100; ++i)
{
ThreadPool.QueueUserWorkItem((_) =>
{
var delayedTime = this.random.Next(10, 500);
var localPostTime = stopWatch.ElapsedMilliseconds;
syncContext.PostDelayed(() =>
{
try
{
var actualDelayedTime = (stopWatch.ElapsedMilliseconds - localPostTime);
Assert.GreaterOrEqual(actualDelayedTime, delayedTime, "Call-back executed too early.");
Assert.LessOrEqual(actualDelayedTime, delayedTime + 100, "Call-back executed too late.");
}
catch (Exception ex)
{
exception = ex;
}
finally
{
lock (syncLock)
{
++completedCount;
if (completedCount == 100 || exception != null)
{
Monitor.Pulse(syncLock);
}
}
}
}, delayedTime);
});
}
Assert.IsTrue(Monitor.Wait(syncLock, 60000), "Unable to complete waiting for posting delayed call-back on multi-threads.");
}
}