by Ray B Dutton (1 Submission)
Category: Windows API Call/Explanation
Difficulty: Intermediate
Date Added: Wed 3rd February 2021
Rating: 
(4 Votes)
Replaces the Visual Basic SendKeys statement which will not work in Vista. Uses the API call to the keybd_event to send characters and control codes. I have not extensively tested this routine, but it works for all the programs I have written to control external programs. The "WAIT" option is handled for compatibility, but is not implemented.
Inputs
Since this subroutine is named SendKeys, in most cases there is no need to re-code. Just place the new SendKeys subroutine in a public section of your project. However, you can no longer depend on the "WAIT" option. It is ignored in the new SendKeys.
Assumes
I did not bother to re-create the triple code SendKeys function such as +(AC). My replacement sends only the control key (+) key and the "A" as a double key, but it sends the "C" as just a capitol "C".
Side Effects
I have not tested this routine in anything other than Visual Basic 5.0. I did not bother with some of the control fuctions like {BREAK}, {PRTSCR}, etc. You may want to.
API DeclarationsDeclare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Long, ByVal dwExtraInfo As Long)
Declare Function GetKeyboardState Lib "user32" (pbKeyState As Byte) As Long
VBcodersPublic Sub SendKeys(St As String, Optional Wait As Boolean)
'*****************************************************************************
'Replacement for the Visual Basic SendKeys function. The optional Wait parameter
'is included for compatibility only, but is ignored. The multiple key
'function indicated by parentheses is handled but only the control key and next
'key are treated as a multiple key stroke, not three. The next character(s)
'is treated as a separate keystroke. The control keys +^% will be recognized
'as standard characters unless they appear as the first character in the
'SendKeys string.
'
'This new subroutine requires the following declarations in your project's form or
'bas module:
'
'Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, _
' ByVal dwFlags As Long, ByVal dwExtraInfo As Long)
'
'Declare Function GetKeyboardState Lib "user32" (pbKeyState As Byte) As Long
'
'*******************************************************************************
Dim vbKCode As Variant
Dim ShiftCtrlAlt As Variant
Dim CapsLockState As Variant
Dim keys(0 To 255) As Byte
'Check the state of the CapsLock button to determine whether to
'send or not send the SHIFT KEY
GetKeyboardState keys(0)
CapsLockState = keys(vbKeyCapital)
start:
'Check for Shift, Ctrl, and Alt
If InStr("+^%", Left$(St$, 1)) > 0 Then
Select Case Left$(St$, 1)
Case "+"
ShiftCtrlAlt = vbKeyShift
Case "^"
ShiftCtrlAlt = vbKeyControl
Case "%"
ShiftCtrlAlt = vbKeyMenu
Case Else
ShiftCtrlAlt = ""
End Select
End If
'Check for Special Keys
If InStr(St$, "{") > 0 Then
P1 = InStr(St$, "{")
P2 = InStr(St$, "}")
SpecialKey$ = Mid$(St$, P1, P2 - P1 + 1)
Select Case SpecialKey$
Case "{BACKSPACE}", "{BS}", "{BKSP}"
vbKCode = vbKeyBack
Case "{DELETE}", "{DEL}"
vbKCode = vbKeyDelete
Case "{DOWN}"
vbKCode = vbKeyDown
Case "{END}"
vbKCode = vbKeyEnd
Case "{ENTER}"
Case "{ESC}"
vbKCode = vbKeyEscape
Case "{HELP}"
vbKCode = vbKeyHelp
Case "{HOME}"
vbKCode = vbKeyHome
Case "{INSERT}", "{INS}"
vbKCode = vbKeyInsert
Case "{LEFT}"
vbKCode = vbKeyLeft
Case "{NUMLOCK}"
vbKCode = vbKeyNumlock
Case "{PGDN}"
vbKCode = vbKeyPageDown
Case "{PGUP}"
vbKCode = vbKeyPageUp
Case "{RIGHT}"
vbKCode = vbKeyRight
Case "{SCROLLLOCK}"
vbKCode = vbKeyScrollLock
Case "{TAB}"
vbKCode = vbKeyTab
Case "{UP}"
vbKCode = vbKeyUp
Case "{F1}"
vbKCode = vbKeyF1
Case "{F2}"
vbKCode = vbKeyF2
Case "{F3}"
vbKCode = vbKeyF3
Case "{F4}"
vbKCode = vbKeyF4
Case "{F5}"
vbKCode = vbKeyF5
Case "{F6}"
vbKCode = vbKeyF6
Case "{F7}"
vbKCode = vbKeyF7
Case "{F8}"
vbKCode = vbKeyF8
Case "{F9}"
vbKCode = vbKeyF9
Case "{F10}"
vbKCode = vbKeyF10
Case "{F11}"
vbKCode = vbKeyF11
Case "{F12}"
vbKCode = vbKeyF12
Case "{F13}"
vbKCode = vbKeyF13
Case "{F14}"
vbKCode = vbKeyF14
Case "{F15}"
vbKCode = vbKeyF15
Case "{F16}"
vbKCode = vbKeyF16
Case Else
vbKCode = ""
Exit Sub
End Select
If ShiftCtrlAlt > 0 Then
GoSub SendWithControl
Else
GoSub SendWithoutControl
End If
If Len(St$) > P2 Then
'If there are more characters in the string,
'remove those keys sent and start over.
St$ = Mid$(St$, P2 + 1)
GoTo start
End If
Exit Sub
End If
'Section to send a Control Key and a Character
Set1$ = ")!@#$%^&*(" 'Characters above the numbers requiring SHIFT KEY
Set2$ = "`-=[]\;',./" 'Other miscellaneous characters
Set3$ = "~_+{}|:" & Chr(34) & "<>?" 'Miscellaneous characters requiring SHIFT KEY
If ShiftCtrlAlt > 0 Then
'Handle the three key problem which uses parentheses
If InStr(St$, "(") > 0 Then
'Strip the Parentheses.
St$ = Mid$(St$, 1, 1) & Mid$(St$, 3, InStr(St$, ")") - 3)
End If
vbKCode = Asc(UCase(Mid$(St$, 2, 1)))
'Check for characters 0 to 9, and A to Z. Scan codes same as ASCII
If (vbKCode >= 48 And vbKCode <= 57) Or (vbKCode >= 65 And vbKCode <= 90) Then
If ShiftCtrlAlt = vbKeyShift Then
'Handle the problem of the CAPSLOCK
If CapsLockState = False Then
GoSub SendWithControl
Else
GoSub SendWithoutControl
End If
Else
GoSub SendWithControl
End If
Else
'Set the scan code for each miscellaneous character
If InStr(Set1$, Mid$(St$, 2, 1)) > 0 Then
vbKCode = 47 + InStr(Set1$, Mid$(St$, 2, 1))
ElseIf InStr(Set2$, Mid$(St$, 2, 1)) > 0 Then
vbKCode = Choose(InStr(Set2$, Mid$(St$, 2, 1)), 192, 189, 187, 219, _
221, 220, 186, 222, 188, 190, 191)
ElseIf InStr(Set3$, Mid$(St$, 2, 1)) > 0 Then
vbKCode = Choose(InStr(Set3$, Mid$(St$, i, 1)), 192, 189, 187, 219, _
221, 220, 186, 222, 188, 190, 191)
End If
End If
'If there are more characters to print, remove the control key
'and the first character and go to the next section. No control characters
'processed beyond this point.
If Len(St$) > 2 Then
St$ = Mid$(St$, 3)
Else
Exit Sub
End If
End If
'********* SEND CHARACTER STRING **********
'Send all remaining characters as text, including control type characters
'such as (+^%{[) etc.
ShiftCtrlAlt = vbKeyShift 'Prepare to send the SHIFT KEY when needed
'Set the scan code for each character and then send it
For i = 1 To Len(St$)
vbKCode = Asc(UCase(Mid$(St$, i, 1)))
If InStr(Set1$, Mid$(St$, i, 1)) > 0 Then
vbKCode = 47 + InStr(Set1$, Mid$(St$, i, 1))
GoSub SendWithControl
ElseIf InStr(Set2$, Mid$(St$, i, 1)) > 0 Then
vbKCode = Choose(InStr(Set2$, Mid$(St$, i, 1)), 192, 189, 187, 219, 221, _
220, 186, 222, 188, 190, 191)
GoSub SendWithoutControl
ElseIf InStr(Set3$, Mid$(St$, i, 1)) > 0 Then
vbKCode = Choose(InStr(Set3$, Mid$(St$, i, 1)), 192, 189, 187, 219, 221, _
220, 186, 222, 188, 190, 191)
GoSub SendWithControl
Else
'Check to see if the character is upper or lower case and then
'determine whether to send the SHIFT KEY based upon whether or not
'the CAPSLOCK is set.
If Asc(Mid$(St$, i, 1)) > vbKCode Then 'If true character is to be lowercase
If CapsLockState = False Then
GoSub SendWithoutControl
Else
GoSub SendWithControl
End If
Else
If CapsLockState = False Then
GoSub SendWithControl
Else
GoSub SendWithoutControl
End If
End If
End If
Next i
Exit Sub
'API call to send a Control Code and a Character
SendWithControl:
keybd_event ShiftCtrlAlt, 0, 0, 0 'Control Key Down
keybd_event vbKCode, 0, 0, 0 'Character Key Down
keybd_event ShiftCtrlAlt, 0, &H2, 0 'Control Key Up
keybd_event vbKCode, 0, &H2, 0 'Character Key Up
Return
'API call to send only one Character
SendWithoutControl:
keybd_event vbKCode, 0, 0, 0 'Character Key Down
keybd_event vbKCode, 0, &H2, 0 'Character Key Up
Return
End Sub
