Solved

Getting text from another program SendMessage? WM_GETTEXT

Posted on 2004-08-01
5
775 Views
Last Modified: 2008-02-01
I am trying to get a large amount of text into my program, from a different program.   I have tried using:

SendMessage progHWND, WM_GETTEXT, 8192, sText

The problem I am having, is the limit to the size of the text buffer.  it's only letting me get a small portion of the text that I need.  Is there a different method that will allow me to get much more?  Or is there a way I can get portions of it at a time?

Thanks in advance.


0
Comment
Question by:TAF2000
  • 2
  • 2
5 Comments
 
LVL 55

Expert Comment

by:Jaime Olivares
ID: 11690302
Hi TAF2000,

Notice that there is a OS limitation in Edit Boxes. 0x7FFF for Win95/98/Me and 0x7FFFFFFF for WinNT/2000/XP
Read at: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/commctls/editcontrols/editcontrolreference/editcontrolmessages/em_setlimittext.asp 

Good luck,
Jaime.
0
 
LVL 17

Accepted Solution

by:
zzzzzooc earned 300 total points
ID: 11690329
>>The problem I am having, is the limit to the size of the text buffer.
Why don't you just increase the size of the buffer?

Form1:
-------------
Option Explicit

Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long

Private Const WM_GETTEXT = &HD
Private Const WM_GETTEXTLENGTH = &HE
Private Sub Form_Load()
    Dim lngHandle As Long, strBuffer As String, lngLen As Long
    'fill our textbox with a lot of text...
    Text1.Text = String(10000, "a")
    'get the amount of text within it..
    lngHandle = Text1.hwnd
    lngLen = SendMessage(lngHandle, WM_GETTEXTLENGTH, 0, 0)
    'increase our buffer to accommodate the text we're about to get...
    strBuffer = Space(lngLen)
    'get text...
    Call SendMessage(lngHandle, WM_GETTEXT, lngLen, ByVal strBuffer)
    'print to debug...
    Debug.Print strBuffer
End Sub



Mind you, controls may have their own limitations. TextBox limits are around 65k.
0
 

Author Comment

by:TAF2000
ID: 11690339
yes, the limt im having problems with is not max int (2147483647) that you refered too..
it is a much lower limitation caused by the string buffer:

Dim sText As String * 8192

it will not let you create a very large string..

so.. is there a way to get around this?  using something else in the sendmessage command?

Thanks
0
 

Author Comment

by:TAF2000
ID: 11690346
zzzzzooc,
just saw your message after replying to jaime's comment.  Will give it a shot.
0
 
LVL 17

Expert Comment

by:zzzzzooc
ID: 11692593
Oh, one more comment. lngLen may need to be lngLen + 1:

If lngLen > 0 Then
    lngLen = lngLen + 1
    'etc...
End If
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

There are many ways to remove duplicate entries in an SQL or Access database. Most make you temporarily insert an ID field, make a temp table and copy data back and forth, and/or are slow. Here is an easy way in VB6 using ADO to remove duplicate row…
If you need to start windows update installation remotely or as a scheduled task you will find this very helpful.
As developers, we are not limited to the functions provided by the VBA language. In addition, we can call the functions that are part of the Windows operating system. These functions are part of the Windows API (Application Programming Interface). U…
This lesson covers basic error handling code in Microsoft Excel using VBA. This is the first lesson in a 3-part series that uses code to loop through an Excel spreadsheet in VBA and then fix errors, taking advantage of error handling code. This l…

914 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

19 Experts available now in Live!

Get 1:1 Help Now