// find the name of the base class for this HWND. If this fails for any reason just return null.
private static string GetBaseClassName(NativeMethods.HWND hwnd)
{
const int OBJID_QUERYCLASSNAMEIDX = unchecked (unchecked ((int)0xFFFFFFF4));
const int QUERYCLASSNAME_BASE = 65536;
if (IsKnownBadWindow(hwnd))
{
return(RealGetWindowClass(hwnd).ToLower(CultureInfo.InvariantCulture));
}
IntPtr result = Misc.SendMessageTimeout(hwnd, UnsafeNativeMethods.WM_GETOBJECT, IntPtr.Zero, (IntPtr)OBJID_QUERYCLASSNAMEIDX);
int index = (int)result;
if (index >= QUERYCLASSNAME_BASE && index - QUERYCLASSNAME_BASE < _classNames.Length)
{
return(_classNames[index - QUERYCLASSNAME_BASE].ToLower(CultureInfo.InvariantCulture));
}
else
{
return(RealGetWindowClass(hwnd).ToLower(CultureInfo.InvariantCulture));
}
}
// OnEventSystemCaptureStart - process an EventSystemCaptureStart WinEvent.
private void OnEventSystemCaptureStart(int eventId, IntPtr hwnd, int idObject, int idChild, uint eventTime)
{
// Deal only with Combolbox dropdowns...
if (Accessible.IsComboDropdown(hwnd))
{
// Need to get id of focused item...
try
{
IntPtr i = Misc.SendMessageTimeout(NativeMethods.HWND.Cast(hwnd), UnsafeNativeMethods.LB_GETCURSEL, IntPtr.Zero, IntPtr.Zero);
Accessible acc = Accessible.Create(hwnd, UnsafeNativeMethods.OBJID_CLIENT, i.ToInt32() + 1);
if (acc == null)
{
return;
}
HandleFocusChange(hwnd, acc, idObject, idChild, eventTime);
}
catch (TimeoutException)
{
// Ignore
}
}
}
