Help in implementing global keyboard hook

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VB

I'm writing a simple program in VB2008 that runs in the system tray. I would like to set a hotkey combination (for instance Ctrl+Alt+Shift+K) that will trigger a subroutine.

So far, I've been able to get the program to respond to a key combination, but only if the form is not minimized to the system tray. Here is some example code to demonstrate:

Imports System.Runtime.InteropServices
Public Partial Class MainForm
	
	Public Const MOD_ALT As Integer = &H1
	Public Const MOD_CONTROL As Integer = &H2
	Public Const MOD_SHIFT As Integer = &H4
	Public Const WM_HOTKEY As Integer = &H312
	
	<DllImport("User32.dll")> _
	Public Shared Function RegisterHotKey(ByVal hwnd As IntPtr, _
                        ByVal id As Integer, ByVal fsModifiers As Integer, _
                        ByVal vk As Integer) As Integer
	End Function
    
	<DllImport("User32.dll")> _
	Public Shared Function UnregisterHotKey(ByVal hwnd As IntPtr, _
                        ByVal id As Integer) As Integer
	End Function	
	
	Public Sub New()
		Me.InitializeComponent()
	End Sub
	
	Sub MainFormLoad(sender As Object, e As EventArgs)
		RegisterHotKey(Me.Handle, 100, MOD_CONTROL + MOD_ALT + MOD_SHIFT, Keys.K)
		ContextMenuStrip1.Enabled = False
	End Sub
    
	Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)
		If m.Msg = WM_HOTKEY Then
		Dim id As IntPtr = m.WParam
		Select Case (id.ToString)
			Case "100"
			MsgBox("Ctrl + Alt + Shift + K was pressed")
			End Select
		End If
		MyBase.WndProc(m)
	End Sub    
	
	Sub MainFormFormClosing(sender As Object, e As FormClosingEventArgs)
		e.Cancel = True
		Me.WindowState = FormWindowState.Minimized
		Me.ShowInTaskbar = False
		ContextMenuStrip1.Enabled = True
	End Sub
	
	Sub ShowToolStripMenuItemClick(sender As Object, e As EventArgs)
		Me.WindowState = FormWindowState.Normal
		Me.ShowInTaskbar = True
		ContextMenuStrip1.Enabled = False
	End Sub
	
	Sub ExitToolStripMenuItemClick(sender As Object, e As EventArgs)
		UnregisterHotKey(Me.Handle, 100)
		End
	End Sub
	
	Sub MainFormSizeChanged(sender As Object, e As EventArgs)
		If Me.WindowState = FormWindowState.Minimized Then
		ShowInTaskbar = False
		ContextMenuStrip1.Enabled = True
		End If
	End Sub
	
End Class

If I change ShowInTaskbar to True in the MainFormSizeChanged handler, the program will respond to the key combination even when minimized to the system tray (presumably because it is still in the taskbar). While this is a solution, its not as 'proper' as it should be.

I think the solution is to use a global keyboard hook, but this is going beyond my level of experience.

I've added a notify icon and context menu script to this code[^](which uses a keyboard hook to capture the printscreen key) and confirmed that the keyboard hook code does work even when minimized to the tray. But I'm having a hard time seeing how to adapt the code to work with my key combination.

A slightly different keyhook implementation can be found in this code[^]. I also added systray functionality to this code and it too works when minimized. But again, I'm not able to make the leap and adapt this to respond to my key combination.

Does anyone have any code suggestions or links that might help me get this working?