I am developing an application which opens and reads an XML document previously embedded in a PowerPoint presentation, or a Word document. In order to read this object (xmlFile as Object
) I have to do:
xmlFile.OLEFormat.DoVerb 1
This opens the package object, and I have another subroutine that gets the open instance of Notepad.exe, and reads its contents in to ADODB stream.
An example of this procedure is available on Google Docs:
XML_Test.pptm.
During this process there is a few seconds window where the Notepad.exe gains focus, and an inadvertent keystroke may cause undesired results or error reading the XML data.
I am looking for one of two things:
MouseKeyboardTest
subroutine, below. Or,For #1: this is the function that I found, which I am leery of using. I am wary of taking this sort of control of the users system. ##Are there any other methods that I might use?##
Private Declare Function BlockInput Lib "USER32.dll" (ByVal fBlockIt As Long) As Long
Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Sub MouseKeyboardTest() 'both keyboard and mouse blocked
BlockInput True ' Turns off Keyboard and Mouse
' Routine goes here
Sleep 5000 ' Optional coding
BlockInput False ' Turns on Keyboard and Mouse
End Sub
For #2: Some background, but the issue seems to be the inability to extract the embedded object reliably using any method other than DoVerb 1
. Since I am dealing with an unsaved document in an application (Notepad) that is immune to my VBA skillz, this seems to be the only way to do this. Full background on that, here:
Extracting an OLEObject (XML Document) from PowerPoint VBA
As you correctly guessed in the comment above that taking the focus away from notepad will solve your problem. The below code does exactly that.
LOGIC:
A. Loop through the shape and get it's name. In your scenario it would be something like Chart Meta XML_fbc9775a-19ea-.txt
B. Use APIs like FindWindow
, GetWindowTextLength
, GetWindow
etc to get the handle of the notepad window using partial caption.
C. Use the ShowWindow
API to minimize the window
Code (tested in VBA-Powerpoint)
Paste this code in a module in the above PPTM
Private Declare Function FindWindow Lib "User32" Alias "FindWindowA" _
(ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function GetWindowText Lib "User32" Alias "GetWindowTextA" _
(ByVal hWnd As Long, ByVal lpString As String, ByVal cch As Long) As Long
Private Declare Function GetWindowTextLength Lib "User32" Alias _
"GetWindowTextLengthA" (ByVal hWnd As Long) As Long
Private Declare Function GetWindow Lib "User32" (ByVal hWnd As Long, _
ByVal wCmd As Long) As Long
Private Declare Function ShowWindow Lib "User32" (ByVal hWnd As Long, _
ByVal nCmdShow As Long) As Long
Private Const GW_HWNDNEXT = 2
Private Const SW_SHOWMINIMIZED = 2
Sub Sample()
Dim shp As Shape
Dim winName As String
Dim Ret As Long
For Each shp In ActivePresentation.Slides(1).Shapes
If shp.Type = msoEmbeddedOLEObject Then
winName = shp.Name
shp.OLEFormat.Activate
Exit For
End If
Next
If winName <> "" Then
Wait 1
If GetHwndFromCaption(Ret, Replace(winName, ".txt", "")) = True Then
Call ShowWindow(Ret, SW_SHOWMINIMIZED)
Else
MsgBox "Window not found!", vbOKOnly + vbExclamation
End If
End If
End Sub
Private Function GetHwndFromCaption(ByRef lWnd As Long, ByVal sCaption As String) As Boolean
Dim Ret As Long
Dim sStr As String
GetHwndFromCaption = False
Ret = FindWindow(vbNullString, vbNullString)
Do While Ret <> 0
sStr = String(GetWindowTextLength(Ret) + 1, Chr$(0))
GetWindowText Ret, sStr, Len(sStr)
sStr = Left$(sStr, Len(sStr) - 1)
If InStr(1, sStr, sCaption) > 0 Then
GetHwndFromCaption = True
lWnd = Ret
Exit Do
End If
Ret = GetWindow(Ret, GW_HWNDNEXT)
Loop
End Function
Private Sub Wait(ByVal nSec As Long)
nSec = nSec + Timer
While nSec > Timer
DoEvents
Wend
End Sub
My understanding is that you have control over how XML file gets embedded into PowerPoint presentation in the first place. Here I do not quite understand why you chose to keep the data you need as contents of an embedded object.
To be sure, the task of getting those contents back is not a piece of cake. Actually, as long as there is no (simple or even moderately difficult) way to call QueryInterface
and use IPersist*
interfaces from VBA, there is just one way to get to contents of embedded object. The way involves following steps:
OLEFormat.DoVerb 1
for that. A better way would be to call OLEFormat.Activate
, but this is irrelevant for your particular problem.Notepad.exe
exposes no such programming model, and you resorted to WinAPI
which is the best choice available.Unfortunately, your current approach has at least 2 flaws:
notepad.exe
leading to possibility of user's interference)..txt
files other than notepad.exe
, your approach is doomed.If you do have control over how embedded object is created then better approach would be to store your XML data in some property of Shape
object. I would use Shape.AlternativeText
(very straightforward to use; shouldn't be used if you export your .pptm
to HTML or have some different scenario where AlternativeText
matters) or Shape.Tags
(this one is probably the most semantically correct for the task) for that.
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