by Steve Register (1 Submission)
Category: Miscellaneous
Compatability: Visual Basic 3.0
Difficulty: Unknown Difficulty
Date Added: Wed 3rd February 2021
Rating: 
(6 Votes)
Allows users to be able to send keystrokes to dos programs running in a windows95 dos box
Inputs
This class has one property, Destination, which needs to be the handle returned from the shell function of the dos program or any program
started with the shell function.
It also has one method called, SendKeys, this is the string to be sent to the destination.
Assumes
Nothing except how to use a class module in their code
Code Returns
N/A
Side Effects
None that I am aware of
API Declarationsnone, everything is done in the class module
VBcodersOption Explicit
'local variable(s) to hold property value(s)
Private mvarDestination As Long 'local copy
Private Const KEYEVENTF_EXTENDEDKEY = &H1
Private Const KEYEVENTF_KEYUP = &H2
Private Const VK_SHIFT = &H10
Private Declare Function OemKeyScan Lib "user32" (ByVal wOemChar As Integer) As Long
Private Declare Function CharToOem Lib "user32" Alias "CharToOemA" (ByVal lpszSrc As String, ByVal lpszDst As String) As Long
Private Declare Function VkKeyScan Lib "user32" Alias "VkKeyScanA" (ByVal cChar As Byte) As Integer
Private Declare Function MapVirtualKey Lib "user32" Alias "MapVirtualKeyA" (ByVal wCode As Long, ByVal wMapType As Long) As Long
Private Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Long, ByVal dwExtraInfo As Long)
Private Sub SendAKey(ByVal keys As String)
Dim vk%
Dim shiftscan%
Dim scan%
Dim oemchar$
Dim dl&
Dim shiftkey%
' Get the virtual key code for this character
vk% = VkKeyScan(Asc(keys)) And &HFF
' See if shift key needs to be pressed
shiftkey% = VkKeyScan(Asc(keys)) And 256
oemchar$ = " " ' 2 character buffer
' Get the OEM character - preinitialize the buffer
CharToOem Left$(keys, 1), oemchar$
' Get the scan code for this key
scan% = OemKeyScan(Asc(oemchar$)) And &HFF
' Send the key down
If shiftkey% = 256 Then
'if shift key needs to be pressed
shiftscan% = MapVirtualKey(VK_SHIFT, 0)
'press down the shift key
keybd_event VK_SHIFT, shiftscan%, 0, 0
End If
'press key to be sent
keybd_event vk%, scan%, 0, 0
' Send the key up
If shiftkey% = 256 Then
'keyup for shift key
keybd_event VK_SHIFT, shiftscan%, KEYEVENTF_KEYUP, 0
End If
'keyup for key sent
keybd_event vk%, scan%, KEYEVENTF_KEYUP, 0
End Sub
Public Sub SendKeys(ByVal keys As String)
Dim x&, t As Integer
'loop thru string to send one key at a time
For x& = 1 To Len(keys)
'activate target application
AppActivate (mvarDestination)
'send one key to target
SendAKey Mid$(keys, x&, 1)
Next x&
End Sub
Public Property Let Destination(ByVal vData As Long)
'used when assigning a value to the property, on the left side of an assignment.
'Syntax: X.Destination = 5
mvarDestination = vData
End Property
Public Property Get Destination() As Long
'used when retrieving value of a property, on the right side of an assignment.
'Syntax: Debug.Print X.Destination
Destination = mvarDestination
End Property
