public async Task InvokeAsync(Action action, DispatcherPriority priority = DispatcherPriority.Normal, CancellationToken ct = default)
{
ThrowOnInvokeIfStateIsInvalid();
var workItem = new DispatcherItem(action);
_queues[(Int32)priority].Enqueue(workItem);
_newWorkSemaphore.Release();
var result = await workItem.WaitAsync(ct);
if (result is Exception ex)
{
throw ex;
}
}
public async Task <TResult> InvokeAsync <TResult>(Func <TResult> func, DispatcherPriority priority = DispatcherPriority.Normal, CancellationToken ct = default) where TResult : class
{
ThrowOnInvokeIfStateIsInvalid();
var workItem = new DispatcherItem(func);
_queues[(Int32)priority].Enqueue(workItem);
_newWorkSemaphore.Release();
var result = await workItem.WaitAsync(ct);
if (result is Exception ex)
{
throw ex;
}
return((TResult)result);
}
public void Run()
{
State = DispatcherState.Running;
while (true)
{
// Wait for new work or dispatcher shutting down
_newWorkSemaphore.Wait();
if (State == DispatcherState.ShuttingDown)
{
foreach (var queue in _queues)
{
foreach (var item in queue)
{
item.SignalFinishedWithException(new OperationCanceledException());
}
}
break;
}
// Pick highest priority work
DispatcherItem dispatcherItem = null;
for (Int32 i = _queues.Length - 1; i >= 0; i--)
{
_queues[i].TryDequeue(out dispatcherItem);
if (dispatcherItem != null)
{
break;
}
}
// This, actually, should never happen
if (dispatcherItem == null)
{
throw new DispatcherException("Work is null");
}
// Execute user action
try
{
if (dispatcherItem.DelegateWithoutResult != null)
{
dispatcherItem.DelegateWithoutResult.Invoke();
dispatcherItem.SignalFinished();
}
else
{
var result = dispatcherItem.DelegateWithResult.Invoke();
dispatcherItem.SignalFinished(result);
}
}
catch (Exception ex)
{
dispatcherItem.SignalFinishedWithException(ex);
}
}
_shutdownTaskCompletionSource.SetResult(null);
}