CustomSynchronizationContext.cs

class CustomSynchronizationContext : SynchronizationContext
{
	public static void Install()
	{
		var currentContext = Current;
		if (currentContext is CustomSynchronizationContext) return;
		WindowsFormsSynchronizationContext.AutoInstall = false;
		SetSynchronizationContext(new CustomSynchronizationContext(currentContext));
	}

	public static void Uninstall()
	{
		var currentContext = Current as CustomSynchronizationContext;
		if (currentContext == null) return;
		SetSynchronizationContext(currentContext.baseContext);
	}

	private WindowsFormsSynchronizationContext baseContext;

	private CustomSynchronizationContext(SynchronizationContext currentContext)
	{
		baseContext = currentContext as WindowsFormsSynchronizationContext  ?? new WindowsFormsSynchronizationContext();
		SetWaitNotificationRequired();
	}

	public override SynchronizationContext CreateCopy() { return this; }
	public override void Post(SendOrPostCallback d, object state) { baseContext.Post(d, state); }
	public override void Send(SendOrPostCallback d, object state) { baseContext.Send(d, state); }
	public override void OperationStarted() { baseContext.OperationStarted(); }
	public override void OperationCompleted() { baseContext.OperationCompleted(); }

	public override int Wait(IntPtr[] waitHandles, bool waitAll, int millisecondsTimeout)
	{
		int result = WaitForMultipleObjectsEx(waitHandles.Length, waitHandles, waitAll, millisecondsTimeout, false);
		if (result == -1) throw new Exception();
		return result;
	}

	[SuppressUnmanagedCodeSecurity]
	[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
	private static extern int WaitForMultipleObjectsEx(int nCount, IntPtr[] pHandles, bool bWaitAll, int dwMilliseconds, bool bAlertable);
}