Sending Keystrokes to Acad LT from Excell VBA

I know that VBA has the ability to send keystrokes to another program,
even if that program isn't programmed to work with VBA. I want to do
this so that I can do some simple programming on AutoCAD LT 2000.

I know I could write the AutoCAD commands to a text file, and then
manually run it as a script from inside Acad LT, but I want to
automate that process.

Another desire (although it is a low priority one) is to read some of
the results of List command. Eg. I send AutoCAD the commands to list
a particular

I can assume that the Acad LT is already open, and the dwg I want to
use is also already open.

The problem I have, how to tell Excel's VBA which program window to
use with the SendKeys statement. Can someone give me a specific
example of how to do this?

Joe Dunfee

 

I"ve made a little bit of progress, but continue to have problems.

I use the following code to activate the AutoCAD window from inside an
Excel VBA routine, and then send keystrokes

AppActivate "AutoCAD", 0
SendKeys "Line 0,0 10,5", false

But the space between the two coordinates are ignored for some reason
and they are merged to say "0,010,5"

So, I tried separating the elements by conctantenating, but that
failed as well. Finally, I used a separate SendKeys command to send
an enter. This works;
=========================
AppActivate "AutoCAD", 0

SendKeys "Line 0,0", False
SendKeys "{enter}", False
SendKeys "10,20", False
SendKeys "{enter}", False
SendKeys "{enter}", True
=========================

That was a bit more cumbersome, but it did work.

Now, I am having problems with other similar routines. For some
reason some of the SendKeys commands seem to be skipped over. The
keystrokes are never sent. No error message or anything.

Any ideas what is happening?

Joe Dunfee

 

Hi Joe,

Try implementing "DoEvents" to help with the missing keystrokes.

I think you would have better luck with posting to the customization
newsgroup.

If you get really stuck, you can email me or contact me through
cadmechanic.com as I don't frequent newsgroups on a regular basis.

Hope that helps.

 

Thanks for the reply. Are the DoEvents are just to kill time between
keystrokes? I started to do some for-next loops, but apparently
wasn't doing enough. I finally went went for 5,000 loops, inside
5,000 loops (25 million loops) and was able to slow it down enought to
watch each command... and it worked!

I've been able to get output from AutoCAD by turning on the log file.
[logifleon] and also making it so that it doesn't pause every screen
when I do a lengthy listing [using qaflags to 2 - this is a non
supported variable that works in version 2000 or earlier. I don't
know its current equivalent]

Joe Dunfee

 

Why don't you write everything to a file in your VBA program and then
ask autocad to process the file with sending keystrokes.
This takes away lot of the monitoring problems and lets you test your
program lots easier.
I do this trick with dos prompts and unix shell commands.

Jan

 

That is what I wanted to do... but the only way I had to get
everything over to VBA is to list the entities to a log file. I can't
do a lot of processing in AutoCAD LT because it has very limited
abilities of this sort compared to the full AutoCAD. Or did I
misunderstand what you were suggesting?

Joe Dunfee

 

Joe
First of all I'd like to mention that autocad has a activex interface
you can use from VBA. I don't know wheter autocad LT has it. You
should check in VBA by clicking tools reference and look for stuff
that starts with autocad.

If you don't find that; sendkeys is the way to go.

emulates keystrokes on the keyboard. Programs who do (part) of the
keyboard processing themselves and don't use the standard windows
messages (wm key down wm key up, wm char...) will not respond as
expected. Also programs who swap focus on keystrokes will not behave
as you would expect. As soon as windows are created you need to insert
delays which are platform dependent. So I prefer to avoid it, if at
all possible. But if it is needed and the program accepts files in and
out you still can have a structured approach. Note that autocad used
to be a dos program and is not 100% windows GUI compliant so I expect
it to have "wierd behaviour"

FI if you want to do your line command "Line 0,0 10,5" I would have
my VBA program create a file "doit.cmd"
then use sendkeys to "run the file" doit.cmd and if I'm interested in
the outcome I would use logging to parse the file afterwards.

I havn't done this with autocad but I have done this successfully with
lots of other programs.
Below I copied some code I use for a dos box called rundoscommand.
the code rundoscommand "dir > log.txt" gives me a file that contans
the output of the dir command. And I know the file is available when
the function returns.

You could create something simular for autocad. RunAutocadCommand.
simularly you could have something like
runautocadcommand "a command to turn logging on" & vbnewline & "Line
0,0 10,5" & vbnewline & "a command to stop logging"
And then some code to parse the log file
The biggest problem you'll have is to know autocad stopped processing
your file. What you should do is investigate the GUI and try to find
out wether there is a easy way to know. FI a windows title changing.
And if nothing does you can have your last comand do something it you
can notice. Something like saveas with a new filename.

To conclude: I would investigate the activex path. If that doesn't
work be prepared for blood sweat and tears. But use files and limit
the direct autocad communication.
Jan


'This function executes a dos command.
'To run several commands at the same time use the vbnewline vatiable
to seperate the commands.
'It works as follows.
'A bat file is created containing the command.
'The bat file is executed.
'We wait for the bat file to exit.
Public Function RunDosCommand(stCommand As String) As Long
Dim stTmpFile As String
stTmpFile = "runcommand.bat"
Open stTmpFile For Output As #2
Print #2, stCommand
Close #2
Dim shell As IWshShell_Class
Set shell = New IWshShell_Class
RunDosCommand = shell.Run(stTmpFile, , True)
End Function

 

Mr Baeyens, thank you for the detailed response.

I did need to go the SendKeys approach, beause I am currently using
AutoCAD LT, and that is really my option. I simply had to slow VBA
down a lot. I did however, reduce the effort inside of VBA by writing
a few short routines using the available macro ability inside of
AutoCAD LT. The process is not something I can really give to another
user, because it still requires several manuals steps. (i.e. run
script from inside AcadLT, then switch to Excel and run VBA Macro,
then choose Log file....etc.)

I have IntelliCAD with VBA, but its VBA is different from AutoCAD and
very poorly documented. But, they are supposed to release an AutoCAD
comptable VBA module later this year. So perhaps I will eventually do
it all from inside IntelliCAD.

Joe Dunfee