Click here to Skip to main content
13,445,901 members (39,558 online)
Click here to Skip to main content
Add your own
alternative version


18 bookmarked
Posted 12 May 2003

MCL Global Hotkey ActiveX control

, 12 May 2003
Rate this:
Please Sign up or sign in to vote.
A system wide hotkey control written in VB6


The attached source code is for a system-wide global hotkey control written in Visual Basic 6, originally posted on the Merrion Computing Downloads.

Registering a hotkey

There are two API calls concerned with registering a system wide hotkey: RegisterHotkey and UnregisterHotkey - the declarations are:

To register the hotkey, you need to specify hwnd - the window which will be notified when the hotkey combination is pressed, id - the unique identifier for the hotkey, fsModifiers - the modifiers of the hotkey (i.e. whether ALT, SHIFT, CTRL or WIN keys are pressed) and finally vKey - the virtual key code for the hot key. The modifiers which can be combined together are:

Listening Out for the hotkey

When a hotkey which has been registered successfully is pressed, the window specified in the hwnd is posted a WM_HOTKEY registered window message. Additionally the lParam parameter holds the modifier and virtual key code in its high and low words respectively.

Visual Basic does not handle the WM_HOTKEY message by default which means that you need to subclass the window hwnd in order to respond to it. To do this, you use the API call SetWindowLong with the index GWL_WNDPROC to replace the existing window procedure with yours.

Using the Control in your Application

To use this control in a Visual Basic application, compile the attached source code and then add an instance of the resulting OCX to your project. Add an instance of the MCLHotkey control to your form and press F4 to set the properties. Then add the code that you want executed when the hotkey is pressed to the HotkeyPressed event:

Private Sub MCLHotkey1_HotkeyPressed()
  Debug.Print "You pressed the hotkey at " & Now
End Sub
'\\ API Calls used in subclassing windows....
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
Private Declare Function DefWindowProc Lib "user32" Alias "DefWindowProcA" _
	(ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, _
	ByVal lParam As Long) As Long
'\\ Window specific information
Private Declare Function GetWindowLongApi Lib "user32" Alias "GetWindowLongA" _
	(ByVal hwnd As Long, ByVal nIndex As Long) As Long
Private Declare Function SetWindowLongApi Lib "user32" Alias "SetWindowLongA" _
	(ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Private Const GWL_WNDPROC = (-4)
Public Function VB_WindowProc(ByVal hwnd As Long, ByVal wMsg As Long, _
	ByVal wParam As Long, ByVal lParam As Long) As Long

Dim VKey As Long
Dim Modifier As Long

If wMsg = WM_HOTKEY Then
    VKey = HiWord(lParam)
    Modifier = LoWord(lParam)
    '\\ Raise an event here to respond to the hotkey
End If

If sWindow.OldWndProc = 0 Then
    VB_WindowProc = DefWindowProc(hwnd, wMsg, wParam, lParam)
    VB_WindowProc = CallWindowProc(sWindow.OldWndProc, hwnd, wMsg, wParam, lParam)
End If

End Function
Public Enum enHotkeyModifiers
    MOD_ALT = &H1
    MOD_SHIFT = &H4
    MOD_WIN = &H8
End Enum
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


  • 12th May, 2003: Initial post


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Duncan Edwards Jones
Software Developer (Senior)
Ireland Ireland
C# / SQL Server developer
Microsoft MVP (Azure) 2017
Microsoft MVP (Visual Basic) 2006, 2007

You may also be interested in...


Comments and Discussions

Generalmisbehave on window vista Pin
arunkumar.1658330-Jan-09 22:19
memberarunkumar.1658330-Jan-09 22:19 
Generalthis is great but Pin
Leerz5-Dec-06 6:16
memberLeerz5-Dec-06 6:16 
GeneralRe: this is great but Pin
Duncan Edwards Jones8-Feb-07 3:51
memberDuncan Edwards Jones8-Feb-07 3:51 
GeneralExcellent Control but a couple of problems Pin
AvoSoftwareTeam29-Oct-05 2:38
memberAvoSoftwareTeam29-Oct-05 2:38 
GeneralRe: Excellent Control but a couple of problems Pin
Duncan Edwards Jones29-Oct-05 6:32
memberDuncan Edwards Jones29-Oct-05 6:32 
GeneralDisable the [Ctrl]+[Esc] keys Pin
Anonymous13-Jan-05 11:46
sussAnonymous13-Jan-05 11:46 
GeneralGreat but... Pin
Q_HAL2-Aug-04 4:36
memberQ_HAL2-Aug-04 4:36 
GeneralNice Ariticle:reason why I rated this excellent Pin
Ipog Gates18-Jan-04 0:45
memberIpog Gates18-Jan-04 0:45 
General.NET Version Pin
Merrion13-Jun-03 0:45
memberMerrion13-Jun-03 0:45 
GeneralRe: .NET Version Pin
Jehosephat22-Nov-04 10:34
memberJehosephat22-Nov-04 10:34 
GeneralRe: .NET Version Pin
Merrion22-Nov-04 12:14
memberMerrion22-Nov-04 12:14 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

Permalink | Advertise | Privacy | Terms of Use | Mobile
Web01-2016 | 2.8.180314.2 | Last Updated 13 May 2003
Article Copyright 2003 by Duncan Edwards Jones
Everything else Copyright © CodeProject, 1999-2018
Layout: fixed | fluid