Gets the handle of the window under the mouse cursor.
Private Type POINTAPI
X As Long
Y As Long
End Type
Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINTAPI) As Long
Private Declare Function WindowFromPoint Lib "user32" (ByVal xPoint As Long, _
ByVal yPoint As Long) As Long
' Return the handle of the window under the mouse cursor.
Function WindowFromMouse() As Long
Dim lpPoint As POINTAPI
GetCursorPos lpPoint
WindowFromMouse = WindowFromPoint(lpPoint.X, lpPoint.Y)
End Function