Windows NT4 and Windows 2000: The F12 key is reserved for use by the debugger at all times, so it should not be registered as a hot key. Even when you are not debugging an application, F12 is reserved in case a kernel-mode debugger or a just-in-time debugger is resident.
Option ExplicitPrivate Const MOD_ALT = &H1
Private Const MOD_CONTROL = &H2
Private Const MOD_SHIFT = &H4
Private Const PM_REMOVE = &H1
Private Const WM_HOTKEY = &H312
Private Type POINTAPI
x As Long
y As Long
End Type
Private Type Msg
hWnd As Long
Message As Long
wParam As Long
lParam As Long
time As Long
pt As POINTAPI
End Type
Private Declare Function RegisterHotKey Lib "user32" (ByVal hWnd As Long, ByVal id As Long, ByVal fsModifiers As Long, ByVal vk As Long) As Long
Private Declare Function UnregisterHotKey Lib "user32" (ByVal hWnd As Long, ByVal id As Long) As Long
Private Declare Function PeekMessage Lib "user32" Alias "PeekMessageA" (lpMsg As Msg, ByVal hWnd As Long, ByVal wMsgFilterMin As Long, ByVal wMsgFilterMax As Long, ByVal wRemoveMsg As Long) As Long
Private Declare Function WaitMessage Lib "user32" () As Long
Private bCancel As Boolean
Private Sub ProcessMessages()
Dim Message As Msg
'loop until bCancel is set to True
Do While Not bCancel
'wait for a message
WaitMessage
'check if it's a HOTKEY-message
If PeekMessage(Message, Me.hWnd, WM_HOTKEY, WM_HOTKEY, PM_REMOVE) Then
WindowState = vbMaximized
Me.SetFocus
End If
'let the operating system process other events
DoEvents
Loop
End Sub
Private Sub Form_Load()
Dim ret As Long
bCancel = False
'register the Ctrl-F hotkey
ret = RegisterHotKey(Me.hWnd, &HBFFF&, MOD_CONTROL, vbKeyF)
'show some information
Me.AutoRedraw = True
Me.Print "按 CTRL＋F 本窗口便被呼叫，并最大化！"
'show the form and
Show
'process the Hotkey messages
ProcessMessages
End Sub
Private Sub Form_Unload(Cancel As Integer)
bCancel = True
'unregister hotkey
Call UnregisterHotKey(Me.hWnd, &HBFFF&)
End Sub
//////////////////////////////////////////////////////////////////
MSDN:
Platform SDK: Windows User Interface
RegisterHotKey
The RegisterHotKey function defines a system-wide hot key. BOOL RegisterHotKey(
HWND hWnd, // handle to window
int id, // hot key identifier
UINT fsModifiers, // key-modifier options
UINT vk // virtual-key code
);
Parameters
hWnd
[in] Handle to the window that will receive WM_HOTKEY messages generated by the hot key. If this parameter is NULL, WM_HOTKEY messages are posted to the message queue of the calling thread and must be processed in the message loop.
id
[in] Specifies the identifier of the hot key. No other hot key in the calling thread should have the same identifier. An application must specify a value in the range 0x0000 through 0xBFFF. A shared dynamic-link library (DLL) must specify a value in the range 0xC000 through 0xFFFF (the range returned by the GlobalAddAtom function). To avoid conflicts with hot-key identifiers defined by other shared DLLs, a DLL should use the GlobalAddAtom function to obtain the hot-key identifier.
fsModifiers
[in] Specifies keys that must be pressed in combination with the key specified by the nVirtKey parameter in order to generate the WM_HOTKEY message. The fsModifiers parameter can be a combination of the following values. Value Meaning
MOD_ALT Either ALT key must be held down.
MOD_CONTROL Either CTRL key must be held down.
MOD_SHIFT Either SHIFT key must be held down.
MOD_WIN Either WINDOWS key was held down. These keys are labeled with the Microsoft Windows logo.
vk
[in] Specifies the virtual-key code of the hot key.
Return Values
If the function succeeds, the return value is nonzero.If the function fails, the return value is zero. To get extended error information, call GetLastError.Res
When a key is pressed, the system looks for a match against all hot keys. Upon finding a match, the system posts the WM_HOTKEY message to the message queue of the thread that registered the hot key. This message is posted to the beginning of the queue so it is removed by the next iteration of the message loop. This function cannot associate a hot key with a window created by another thread. RegisterHotKey fails if the keystrokes specified for the hot key have already been registered by another hot key. If the window identified by the hWnd parameter already registered a hot key with the same identifier as that specified by the id parameter, the new values for the fsModifiers and vk parameters replace the previously specified values for these parameters. Windows NT4 and Windows 2000: The F12 key is reserved for use by the debugger at all times, so it should not be registered as a hot key. Even when you are not debugging an application, F12 is reserved in case a kernel-mode debugger or a just-in-time debugger is resident.
ret = RegisterHotKey(Me.hWnd, &HBFFF&, 0, vbKeyF11)
但是，不能用F12来注册，即使你用了F12也是无效的！！！
还有个问题，你的程序只能设置一个热键，如何设置F9,F10,F11三个热键呢？
Private Const MOD_CONTROL = &H2
Private Const MOD_SHIFT = &H4
Private Const PM_REMOVE = &H1
Private Const WM_HOTKEY = &H312
Private Type POINTAPI
x As Long
y As Long
End Type
Private Type Msg
hWnd As Long
Message As Long
wParam As Long
lParam As Long
time As Long
pt As POINTAPI
End Type
Private Declare Function RegisterHotKey Lib "user32" (ByVal hWnd As Long, ByVal id As Long, ByVal fsModifiers As Long, ByVal vk As Long) As Long
Private Declare Function UnregisterHotKey Lib "user32" (ByVal hWnd As Long, ByVal id As Long) As Long
Private Declare Function PeekMessage Lib "user32" Alias "PeekMessageA" (lpMsg As Msg, ByVal hWnd As Long, ByVal wMsgFilterMin As Long, ByVal wMsgFilterMax As Long, ByVal wRemoveMsg As Long) As Long
Private Declare Function WaitMessage Lib "user32" () As Long
Private bCancel As Boolean
Private Sub ProcessMessages()
Dim Message As Msg
'loop until bCancel is set to True
Do While Not bCancel
'wait for a message
WaitMessage
'check if it's a HOTKEY-message
If PeekMessage(Message, Me.hWnd, WM_HOTKEY, WM_HOTKEY, PM_REMOVE) Then
Select Case Message.wParam
Case &HBFFF&
WindowState = vbMaximized
Case &HC000&
WindowState = vbMinimized
Case &HC001&
WindowState = vbNormal
Case Else
End Select
Me.SetFocus
End If
'let the operating system process other events
DoEvents
Loop
End Sub
Private Sub Form_Load()
Dim ret As Long
bCancel = False
'register the hotkey:F9~F11
Call RegisterHotKey(Me.hWnd, &HBFFF&, 0, vbKeyF9) 'vbMaximized
Call RegisterHotKey(Me.hWnd, &HC000&, 0, vbKeyF10) 'vbMinimized
Call RegisterHotKey(Me.hWnd, &HC001&, 0, vbKeyF11) 'vbNormal
'show some information
Me.AutoRedraw = True
Me.Print "按 F9 本窗口便被呼叫，并最大化！" & vbCrLf & "按 F10 本窗口便被呼叫，并最小化！" & vbCrLf & "按 F11 本窗口便被呼叫，并正常化！"
'show the form and
Show
'process the Hotkey messages
ProcessMessages
End Sub
Private Sub Form_Unload(Cancel As Integer)
bCancel = True
'unregister hotkey
Call UnregisterHotKey(Me.hWnd, &HBFFF&)
End Sub