程序置顶

API 声明：

Private Declare Function SetWindowPos Lib "user32" (ByVal hwnd As Long, ByVal hWndInsertAfter As Long, ByVal X As Long, ByVal Y As Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long) As Long

需要置顶时候的代码：
SetWindowPos Me.hwnd, -1, 0, 0, 0, 0, 3

取消置顶的代码：
SetWindowPos Me.hwnd, -2, 0, 0, 0, 0, 3