将About加入窗口的系统菜单

如果能把关于软件的一些信息（About Me）加入窗口的系统菜单是不是很酷啊！
其实这是个很简单的操作，Let's go！

1.添加一个模块（SubClass）
'''''''''''''''''''''''''''''''''''''''
Option Explicit
'有关系统菜单的API
Public Declare Function GetSystemMenu Lib "user32" (ByVal hWnd As Long, ByVal bRevert As Long) As Long
Public Declare Function InsertMenu Lib "user32" Alias "InsertMenuA" (ByVal hMenu As Long, ByVal nPosition As Long, ByVal wFlags As Long, ByVal wIDNewItem As Long, ByVal lpNewItem As Any) As Long

Public Const MF_BYCOMMAND = &H0&
Public Const MF_BYPOSITION = &H400&
Public Const MF_STRING = &H0&
Public Const MF_SEPARATOR = &H800&

'有关窗口的消息处理的API
Private Declare Function SetWindowLong Lib "user32" Alias _
        "SetWindowLongA" (ByVal hWnd As Long, ByVal nIndex _
        As Long, ByVal dwNewLong As Long) As Long
       
Private Declare Function CallWindowProc Lib "user32" Alias _
        "CallWindowProcA" (ByVal lpPrevWndFunc As Long, ByVal _
        hWnd As Long, ByVal Msg As Long, ByVal wParam As _
        Long, ByVal lParam As Long) As Long
       
Const GWL_WNDPROC = (-4&)
Const WM_SYSCOMMAND = &H112
Const WM_DESTROY = &H2

Dim PrevWndProc&

Public Sub Init(hWnd As Long)
  PrevWndProc = SetWindowLong(hWnd, GWL_WNDPROC, AddressOf SubWndProc)
End Sub

Public Sub Terminate(hWnd As Long)
  Call SetWindowLong(hWnd, GWL_WNDPROC, PrevWndProc)
End Sub

Private Function SubWndProc(ByVal hWnd As Long, ByVal Msg As Long, _
                            ByVal wParam As Long, ByVal lParam As Long) _
                            As Long
 
  If Msg = WM_DESTROY Then Terminate (Form1.hWnd)
 
  If Msg = WM_SYSCOMMAND Then
     If wParam = 2002 Then
        MsgBox "我是40Star", vbInformation, "hia..hia..."
     End If
  End If
 
  SubWndProc = CallWindowProc(PrevWndProc, hWnd, Msg, wParam, lParam)
End Function

2.在窗口的load事件中加入
'''''''''''''''''''''''''''''''''''''''
Private Sub Form_Load()
   InsertMenu GetSystemMenu(Me.hWnd, False), 0, MF_BYPOSITION Or MF_SEPARATOR, 2001, "" '加入一条分割线
   InsertMenu GetSystemMenu(Me.hWnd, False), 0, MF_BYPOSITION Or MF_STRING, 2002, "About Me(&A)"  '加入About me菜单在系统菜单中
   Call Init(Me.hWnd)
End Sub

3.在窗口的Unload事件中加入
'''''''''''''''''''''''''''''''''''''''
Private Sub Form_Unload(Cancel As Integer)
   Call Terminate(Me.hWnd)
End Sub

OK啦！运行一下吧，是不是很好玩                  ：）
在Win2000 + Vb6中调试通过

Good Luck