/// <summary>
/// Runs the action inside a message loop and continues pumping messages
/// as long as any asynchronous operations have been registered
/// </summary>
public static void Run(Action asyncAction)
{
using (InstallerAndRestorer.Install())
{
// InstallerAndRestorer ensures the WinForms context is installed
// capture that WinFormsContext
var winFormsContext = SynchronizationContext.Current;
// wrap the WinForms context in our own decorator context and install that
var asyncVoidContext = new AsyncVoidSyncContext(winFormsContext);
SynchronizationContext.SetSynchronizationContext(asyncVoidContext);
// queue up the first message before we start running the loop
var message = new AsyncActionLaunchMessage(asyncAction, asyncVoidContext);
asyncVoidContext.Post(message.LaunchMessageImpl, state: null);
// run the actual WinForms message loop
Application.Run();
}
}
public void LaunchMessageImpl()
{
// wrap the WPF context in our own decorator context and install that
this.asyncVoidContext = new AsyncVoidSyncContext(SynchronizationContext.Current, frame);
SynchronizationContext.SetSynchronizationContext(asyncVoidContext);
// now invoke our taskFunction and store the result
// Do an explicit increment/decrement.
// Our sync context does a check on decrement, to see if there are any
// outstanding asynchronous operations (async void methods register this correctly).
// If there aren't any registerd operations, then it will exit the loop
asyncVoidContext.OperationStarted();
try
{
asyncAction.Invoke();
}
finally
{
asyncVoidContext.OperationCompleted();
}
}
public AsyncActionLaunchMessage(Action asyncAction, AsyncVoidSyncContext postingContext)
{
this.asyncAction = asyncAction;
this.postingContext = postingContext;
}
