Use MapVirtualKeyA with Shift and Ctrl Alt

Question

I have found this page for a function that converts a given keycode in to the corresponding charcater, depending on the system language and keyboard layout. I tested it (in PowerPoint using VBA) and it works, except I don't know how to tell the function that Shift or Ctrl + Alt are being pressed and therefore the function should then return a different result. Say for instance: The keycode 51 corresponds to the number 3, when I pass it to the function, it returns 3. But what if the user is pressing the Shift key? It should return # (or a different character, depending on the keyboard layout, etc.)

So, I know how to check if Shift or Ctrl + Alt are being pressed, but what I don't know is how to tell the function that the keys are being pressed.

I put the following code in a module:

Public Declare PtrSafe Function MapVirtualKeyA Lib "user32" (ByVal uCode As Long, ByVal uMapType As Long) As Integer

And then in the slide's code I put:

Sub test()

    MsgBox Chr(MapVirtualKeyA(vbKey3, 2)) ' always returns 3, even when pressing shift or ctrl + alt

End Sub

I want to know what I have to change in my code so that function knows that Shift or Ctrl + Alt are being pressed.

Thanks in advance.

Answer 1

You could use ToAscii API.

Option Explicit

Private Declare PtrSafe Function ToAscii Lib "user32" (ByVal uVirtKey As Long, ByVal uScanCode As Long, lpbKeyState As Byte, lpChar As LongPtr, ByVal uFlags As Long) As Long
Private Declare PtrSafe Function MapVirtualKeyA Lib "user32" (ByVal uCode As Long, ByVal uMapType As Long) As Long

Sub Test()
    Debug.Print GetCharacterFromVK(uVirtKey:=vbKey3, shiftDown:=True)
End Sub

Function GetCharacterFromVK(uVirtKey As Long _
    , Optional shiftDown As Boolean = False _
    , Optional ctrlDown As Boolean = False _
    , Optional altDown As Boolean = False _
) As String
    'https://learn.microsoft.com/en-us/windows/win32/inputdev/virtual-key-codes
    Const VK_SHIFT = &H10   'SHIFT key
    Const VK_CONTROL = &H11 'CTRL key
    Const VK_MENU = &H12    'ALT key
    '
    Dim keyState(0 To 255) As Byte
    Dim buffer As String: buffer = Space$(2)
    '
    'Set Key States by setting the high-order bit of the byte
    If shiftDown Then keyState(VK_SHIFT) = &H80
    If ctrlDown Then keyState(VK_CONTROL) = &H80
    If altDown Then keyState(VK_MENU) = &H80
    '
    'Populate buffer
    Select Case ToAscii(uVirtKey, MapVirtualKeyA(uVirtKey, 0), keyState(0), ByVal StrPtr(buffer), 0)
    Case 0
        'The specified virtual key has no translation for the current state of the keyboard
        GetCharacterFromVK = vbNullString
    Case 1
        'One character was copied to the buffer
        GetCharacterFromVK = Left$(buffer, 1)
    Case 2
        'Two characters were copied to the buffer
        GetCharacterFromVK = buffer
    End Select
End Function