Our software has worked fine before in VS2010 but we've had to upgrade and figured we'd lash out and upgrade to VS2022 and leverage what is new to .NET 4.8 framework.
We had an existing keyboard hook library that allows our software to control our machines via keyboard, a global hook so far has been the best answer in VS2010 running .NET 4.0.
Just not sure why this is suddenly an issue in VS2022.
The code for doing this is quite Common and general, i'll include it here:
Public Class KeyboardHook
<DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)>
Private Overloads Shared Function SetWindowsHookEx(ByVal idHook As Integer, ByVal HookProc As KBDLLHookProc, ByVal hInstance As IntPtr, ByVal wParam As Integer) As Integer
End Function
<DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)>
Private Overloads Shared Function CallNextHookEx(ByVal idHook As Integer, ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
End Function
<DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)>
Private Overloads Shared Function UnhookWindowsHookEx(ByVal idHook As Integer) As Boolean
End Function
<StructLayout(LayoutKind.Sequential)>
Private Structure KBDLLHOOKSTRUCT
Public vkCode As UInt32
Public scanCode As UInt32
Public flags As KBDLLHOOKSTRUCTFlags
Public time As UInt32
Public dwExtraInfo As UIntPtr
End Structure
<Flags()>
Private Enum KBDLLHOOKSTRUCTFlags As UInt32
LLKHF_EXTENDED = &H1
LLKHF_INJECTED = &H10
LLKHF_ALTDOWN = &H20
LLKHF_UP = &H80
End Enum
Public Shared Event KeyDown(ByVal Key As Keys)
Public Shared Event KeyUp(ByVal Key As Keys)
Private Const WH_KEYBOARD_LL As Integer = 13
Private Const HC_ACTION As Integer = 0
Private Const WM_KEYDOWN = &H100
Private Const WM_KEYUP = &H101
Private Const WM_SYSKEYDOWN = &H104
Private Const WM_SYSKEYUP = &H105
Private Const VK_NUMPAD0 = &H60
Private Const VK_NUMPAD1 = &H61
Private Const VK_NUMPAD2 = &H62
Private Const VK_NUMPAD3 = &H63
Private Const VK_NUMPAD4 = &H64
Private Const VK_NUMPAD5 = &H65
Private Const VK_NUMPAD6 = &H66
Private Const VK_NUMPAD7 = &H67
Private Const VK_NUMPAD8 = &H68
Private Const VK_NUMPAD9 = &H69
Private Delegate Function KBDLLHookProc(ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
Private KBDLLHookProcDelegate As KBDLLHookProc = New KBDLLHookProc(AddressOf KeyboardProc)
Private HHookID As IntPtr = IntPtr.Zero
Private Function KeyboardProc(ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
If (nCode = HC_ACTION) Then
Dim struct As KBDLLHOOKSTRUCT
Select Case wParam
Case WM_KEYDOWN, WM_SYSKEYDOWN
RaiseEvent KeyDown(CType(CType(Marshal.PtrToStructure(lParam, struct.GetType()), KBDLLHOOKSTRUCT).vkCode, Keys))
Case WM_KEYUP, WM_SYSKEYUP
RaiseEvent KeyUp(CType(CType(Marshal.PtrToStructure(lParam, struct.GetType()), KBDLLHOOKSTRUCT).vkCode, Keys))
End Select
End If
Return CallNextHookEx(IntPtr.Zero, nCode, wParam, lParam)
End Function
Public Sub SetHook()
Try
HHookID = SetWindowsHookEx(WH_KEYBOARD_LL, KBDLLHookProcDelegate, System.Runtime.InteropServices.Marshal.GetHINSTANCE(System.Reflection.Assembly.GetExecutingAssembly.GetModules()(0)).ToInt32, 0)
'HHookID = SetWindowsHookEx(WH_KEYBOARD_LL, KBDLLHookProcDelegate, Marshal.GetHINSTANCE(System.Reflection.Assembly.GetExecutingAssembly.GetModules()(0)).ToInt32, 0)
If HHookID = IntPtr.Zero Then
Throw New Exception("Could not set keyboard hook")
End If
Catch ex As Exception
MsgBox("keyboard hook Error: " & ex.Message)
End Try
End Sub
Public Sub UnHook()
If Not HHookID = IntPtr.Zero Then
UnhookWindowsHookEx(HHookID)
End If
End Sub
End Class
The error appears to be in the SetHook method where the HHookID is being set by the SetWindowsHookEx()
It returns a "Arithmetic operation resulted in an overflow" error.
The actual value returned is a massive negative number.
I have tried enabling "Ignore integer overflow checks" in project settings but this still returns the exception and also, of course, does not hook the keyboard.
To save some time, I'd love to keep working on VS2022 as it is moving forward so a solution would be good. :)
I Also tried following the path of Disabling VSHost but I see there is no option for it in VS2022 under the Debugging section of the project.
Does anyone have any ideas?
Thanks to Hans we have a solution. Good spot Hans!
To confirm, the old code worked on VS2010, .NET 4.0
Platform is set to AnyCPU to keep it universal.
Updated code: