用VB編寫一個彈出菜單類

類的名稱為cPopupMenu
    Option Explicit
     ´
     Private Type POINT
     x As Long
     y As Long
     End Type
     ´
     Private Const MF_ENABLED = &H0&
     Private Const MF_SEPARATOR = &H800&
     Private Const MF_STRING = &H0&
     Private Const TPM_RIGHTBUTTON = &H2&
     Private Const TPM_LEFTALIGN = &H0&
     Private Const TPM_NONOTIFY = &H80&
     Private Const TPM_RETURNCMD = &H100&
     Private Declare Function CreatePopupMenu Lib "user32" () As Long
     Private Declare Function AppendMenu Lib "user32" Alias "AppendMenuA" (ByVal hMenu As Long, ByVal wFlags As Long, ByVal wIDNewItem As Long, ByVal sCaption As String) As Long
     Private Declare Function TrackPopupMenu Lib "user32" (ByVal hMenu As Long, ByVal wFlags As Long, ByVal x As Long, ByVal y As Long, ByVal nReserved As Long, ByVal hwnd As Long, nIgnored As Long) As Long
     Private Declare Function DestroyMenu Lib "user32" (ByVal hMenu As Long) As Long
     Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINT) As Long
     Private Declare Function GetForegroundWindow Lib "user32" () As Long
     Private Declare Function GetMenuString Lib "user32" Alias "GetMenuStringA" (ByVal hMenu As Long, ByVal wIDItem As Long, ByVal lpString As String, ByVal nMaxCount As Long, ByVal wFlag As Long) As Long
     Private mSelMenuString As String
     Public Property Get SelMenuString() As String
     SelMenuString = mSelMenuString
     End Property
     ´
     Public Function Popup(ParamArray param()) As Long
     Dim iMenu As Long
     Dim hMenu As Long
     Dim nMenus As Long
     Dim p As POINT
    ´ get the current cursor pos in screen coordinates
     GetCursorPos p
    ´ create an empty popup menu
     hMenu = CreatePopupMenu()
    ´ determine # of strings in paramarray
     nMenus = 1 + UBound(param)
    ´ put each string in the menu
     For iMenu = 1 To nMenus
     ´ the AppendMenu function has been superseeded by the InsertMenuItem
     ´ function, but it is a bit easier to use.
     If Trim$(CStr(param(iMenu - 1))) = "-" Then
     ´ if the parameter is a single dash, a separator is drawn
     AppendMenu hMenu, MF_SEPARATOR, iMenu, ""
     Else
     AppendMenu hMenu, MF_STRING + MF_ENABLED, iMenu, CStr(param(iMenu - 1))
     End If
     Next iMenu