[VB]全局钩子

Option Explicit

Private Declare Function CallNextHookEx Lib "user32" (ByVal hHook As Long, ByVal ncode As Long, ByVal wParam As Long, lParam As Any) As Long
Private Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Long, ByVal lpfn As Long, ByVal hmod As Long, ByVal dwThreadId As Long) As Long
Private Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Long) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
Private Declare Function FindWindow Lib "user32 " Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long

Private Type PKBDLLHOOKSTRUCT
        VKCode   As Long
        scanCode   As Long
        flags   As Long
        time   As Long
        dwExtraInfo   As Long
End Type

Private Const WH_KEYBOARD_LL = 13
Private Const HC_ACTION = 0
Private Const WM_KEYDOWN = &H100
Private Const VK_SNAPSHOT = &H2C
Private PrevHook As Long

   
Public Function LowLevelKeyboardProc(ByVal ncode As Long, ByVal wParam As Long, ByVal lParam As Long) As Long

    If ncode = HC_ACTION Then
        If wParam = WM_KEYDOWN Then
   
            Dim p As PKBDLLHOOKSTRUCT
            CopyMemory p, ByVal lParam, Len(p)

            If p.VKCode = VK_XXX Then ’when XXX Key pressed cancel

                LowLevelKeyboardProc = -1
                Exit Function
            End If
        End If
    End If
   
    CallNextHookEx WH_KEYBOARD_LL, ncode, wParam, lParam

End Function

Public Sub Hook()

    PrevHook = SetWindowsHookEx(WH_KEYBOARD_LL, AddressOf LowLevelKeyboardProc, App.hInstance, 0)

End Sub

Public Sub ReleaseHook()

    Call UnhookWindowsHookEx(PrevHook)

End Sub