Screen Scraping, Spy++ & the GDI

[Mark Everett]

Hi all,

I am writing a program which needs to obtain data from various windows
applications.

I have had success with the first application using FindWindow and
GetWindowText as well as sending messages to listviews and listboxes
to retrieve their contents.

I used Spy++ to find the window class and then wrote a program to find
the elements handle and then communicate with it via window messages.
The problem is that with some of the applications all that Spy++ picks
up is the handle to the main window. A couple of children exist but
they do not appear to be anything familiar. Therefore I aren't sure
how to grab the data. One example is an item which looks like a
listview but all I can find as children to the window is a "web
window" class.

Also what about text which is drawn onto the window - I guess this is
done using the GDI. Is it actually possible to find out text content
of this kind of display? I take it once rendered this information is
not available. I am guessing it is the GDI or maybe a DirectDraw
surface as if it was a label it Spy++ would be able to find it would
it not?

If anyone has any ideas on how I can scrape these items then I would
appreciate it. The data is gathered from an internet based source on
all these applications but port sniffing seems to reveal although most
use HTTP the data is encrypted and I have no idea how to decrypt it -
I take it it's pretty much impossible unless your a hacking expert?

Thanks for your time
Mark

[Bonj]

Spy++ can only gain information on things that have an
HWND. A windowless ActiveX control, or something like a VB
label control, doesn't have an hwnd. Instead, it just
paints on to the hdc of its container. Therefore, Spy++
can have no concept that it is a unique entity.

-----Original Message-----
Hi all,
I am writing a program which needs to obtain data from

various windows

applications.
I have had success with the first application using

FindWindow and

GetWindowText as well as sending messages to listviews

and listboxes

to retrieve their contents.
I used Spy++ to find the window class and then wrote a

program to find

the elements handle and then communicate with it via

window messages.

The problem is that with some of the applications all

that Spy++ picks

up is the handle to the main window. A couple of

children exist but

they do not appear to be anything familiar. Therefore I

aren't sure

how to grab the data. One example is an item which looks

like a

listview but all I can find as children to the window is

a "web

window" class.
Also what about text which is drawn onto the window - I

guess this is

done using the GDI. Is it actually possible to find out

text content

of this kind of display? I take it once rendered this

information is

not available. I am guessing it is the GDI or maybe a

DirectDraw

surface as if it was a label it Spy++ would be able to

find it would

it not?
If anyone has any ideas on how I can scrape these items

then I would

appreciate it. The data is gathered from an internet

based source on

all these applications but port sniffing seems to reveal

although most

use HTTP the data is encrypted and I have no idea how to

decrypt it -

I take it it's pretty much impossible unless your a

hacking expert?

Thanks for your time
Mark
.

[Mark Everett]

Hi Bonj,

Thanks for the reply!

Right that's what I thought to be honest. If someone is using a label
control or DrawText directly or something similar then I take it there
is no way that I can scrape that information?

I originally thought a label would have it's own hwnd but thinking
about it there isn't really any need. Are there any other techniques
possible that I can use to gather this information?

Cheers
Mark

Post by Bonj
Spy++ can only gain information on things that have an
HWND. A windowless ActiveX control, or something like a VB
label control, doesn't have an hwnd. Instead, it just
paints on to the hdc of its container. Therefore, Spy++
can have no concept that it is a unique entity.

Previous message removed to save space!