private static void EnsureSystemEvents(bool requireHandle, bool throwOnRefusal)
{
if (systemEvents == null)
{
lock (procLockObject)
{
if (systemEvents == null)
{
if (Thread.GetDomain().GetData(".appDomain") != null)
{
if (throwOnRefusal)
{
throw new InvalidOperationException(SR.GetString("ErrorSystemEventsNotSupported"));
}
}
else
{
if (!UserInteractive || (Thread.CurrentThread.GetApartmentState() == ApartmentState.STA))
{
systemEvents = new SystemEvents();
systemEvents.Initialize();
}
else
{
eventWindowReady = new ManualResetEvent(false);
systemEvents = new SystemEvents();
windowThread = new Thread(new ThreadStart(systemEvents.WindowThreadProc));
windowThread.IsBackground = true;
windowThread.Name = ".NET SystemEvents";
windowThread.Start();
eventWindowReady.WaitOne();
}
if (requireHandle && (systemEvents.windowHandle == IntPtr.Zero))
{
throw new ExternalException(SR.GetString("ErrorCreateSystemEvents"));
}
startupRecreates = false;
}
}
}
}
}
private static void EnsureSystemEvents(bool requireHandle, bool throwOnRefusal) {
// The secondary check here is to detect asp.net. Asp.net uses multiple
// app domains to field requests and we do not want to gobble up an
// additional thread per domain. So under this scenario SystemEvents
// becomes a nop.
//
if (systemEvents == null) {
lock (procLockObject) {
if (systemEvents == null) {
if (Thread.GetDomain().GetData(".appDomain") != null) {
if (throwOnRefusal) {
throw new InvalidOperationException(SR.GetString(SR.ErrorSystemEventsNotSupported));
}
return;
}
// If we are creating system events on a thread declared as STA, then
// just share the thread.
//
if (!UserInteractive || Thread.CurrentThread.GetApartmentState() == ApartmentState.STA) {
systemEvents = new SystemEvents();
systemEvents.Initialize();
}
else {
eventWindowReady = new ManualResetEvent(false);
systemEvents = new SystemEvents();
windowThread = new Thread(new ThreadStart(systemEvents.WindowThreadProc));
windowThread.IsBackground = true;
windowThread.Name = ".NET SystemEvents";
windowThread.Start();
eventWindowReady.WaitOne();
}
if (requireHandle && systemEvents.windowHandle == IntPtr.Zero) {
// In theory, it's not the end of the world that
// we don't get system events. Unfortunately, the main reason windowHandle == 0
// is CreateWindowEx failed for mysterious reasons, and when that happens,
// subsequent (and more important) CreateWindowEx calls also fail.
// See ASURT #44424 for a rather lengthy discussion of this.
throw new ExternalException(SR.GetString(SR.ErrorCreateSystemEvents));
}
startupRecreates = false;
}
}
}
}