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@BlackBox_ wrote:
I'm just a CAD user who does production daily, but I've found much more than a hobby in programming... I'm fortunate to have been given much help in the few short years I've been coding... And I strive to give back as often as time permits.
...
Kudos:
1+
Cheers
Henrique
@hmsilva wrote:
@BlackBox_ wrote:I'm just a CAD user who does production daily, but I've found much more than a hobby in programming... I'm fortunate to have been given much help in the few short years I've been coding... And I strive to give back as often as time permits.
...
Kudos:
1+
Cheers
Henrique
That is very kind of you, Henrique - If only I had more friends like you here.
Cheers
@BlackBox_ wrote:
...If only I had more friends like you here....
A life journey isn't made only in one forum...
But, I am sure you have.
Cheers
Henrique
@BlackBox
Is nice to hear the RenderMan again! 
@Einsuner30
my apologies for hijack this thread! 
Welcome to the Autodesk Forums!
In addition to what have been written, a good way to improve your knowledge, is stay in this forum, trying to solve the problems/questions that are posted, and learn from the solutions...
Henrique
Ok!
here is one thing that i have in mind.
i wanna greate an application.
Sipmple explanation is:
It should open many drawings, find certain block attribute in it, change it, save the drawing and that is it
I'm very beginner in Autolisp, but i read an old book and i understand a bit about that.
So next steps must be made:
First i should make a dialog, where i can chosse certain drawings
2. program should open these drawings
3. It should start searching block attribitues in drawings
4. open these attributes, do some if functions and then change the data and close the block attribiutes
4. Save the drawing and move on to other.
So i should start with first one and try to make dialog and open these drawings?
Right?
Any good examples for that?
Cheers
martin
@bhull1985 wrote:To do that you'd need a few different files. A script, a .bat, and your lisp routine.
A .bat file will be the file that control the action behind windows (the operating system), it's what you will use to invoke your .scr (script) which in turn will invoke your lisp routine and the command that runs it, along with any other controls you'd like to modify each drawing with such as Zoom+extents, Qsave and Quit.
I would strongly advise against the use of a Batch file to iterate over a set of drawings to be processed - this form of batch processing can be easily achieved using only an AutoCAD Script and suitable AutoLISP program (indeed, for some minor tasks, the AutoLISP program may not even be required).
By using a Batch file, it becomes necessary to repeatedly terminate & launch the entire AutoCAD application, a process that is incredibly slow & inefficient; whereas, when using an AutoCAD Script file to iterate over a set of drawings, a single instance of the AutoCAD application is all that is required and drawings may be closed and opened within the same session.
This is in fact the method that I use when performing an operation to modify a set of drawings (that is, when ObjectDBX is unsuitable for the task). By using a Script file in conjunction with an AutoLISP program, one can exploit the batch processing ability of the Script whilst harnessing the superior power, control & error trapping afforded by an AutoLISP program. This method is further demonstrated by my Batch Attribute Editor program.
@bhull1985 wrote:
Perhaps he would be so kind as to explain to the newer people *HOW* it's possible to have a script do what was described there? As the wheel was invented before the ferrari, and the title clearly states "Autolisp beginners exercises", that may be helpful.
Sure -
To follow the method I have described above, you would essentially require two files: the AutoCAD Script to open, load & run the AutoLISP program, save & close each drawing to be processed; and an AutoLISP file containing the program or function to be evaluated on each drawing.
As noted earlier, for relatively simple tasks, the separate AutoLISP program may not even be required, since the operations could be performed directly using the Script (since a Script file is merely a list of AutoCAD commands to be automatically entered consecutively at the command-line) - indeed, without access to AutoLISP customisation, this is how those unfortunate LT users would need to proceed.
To give an example, consider the following AutoLISP function:
(defun myfunction ( )
(entmake '((0 . "LINE") (10 0.0 0.0 0.0) (11 1.0 1.0 0.0)))
(princ)
)
This function will simply construct a LINE entity in the active drawing layout from (0,0) to (1,1). You can test this by loading the code and typing (myfunction) at the AutoCAD command-line to evaluate the function.
Of course, this is an incredibly simple example, but the program could potentially be any program or function which does not require user input (there is one exception to this rule: since, as noted above, a Script file is merely a list of AutoCAD commands entered at the command-line, if the AutoLISP program submits a nil to the command-line, to cancel a command, this will terminate the Script evaluation).
Now, let's assume that we wish to evaluate the above function on a set of drawings.
Consider the following Script file:
_.open "C:/Drawing1.dwg" (load "myfunction.lsp" nil) (if myfunction (myfunction)) _.qsave _.close _.open "C:/Drawing2.dwg" (load "myfunction.lsp" nil) (if myfunction (myfunction)) _.qsave _.close _.open "C:/Drawing3.dwg" (load "myfunction.lsp" nil) (if myfunction (myfunction)) _.qsave _.close
The above Script assumes that the aforementioned AutoLISP function has been saved to an AutoLISP file with filename myfunction.lsp and that this file resides either in the same directory as the set of drawings to be processed [C:] or within an AutoCAD Support File Search Path.
The Script itself would be saved with an arbitrary filename and in an arbitrary location, but with a .scr extension.
When analysing the Script file itself, note that a space or new-line in a Script represents the user pressing Enter at the command-line. The fact that the operations for each drawing are on a new-line in the Script is merely for clarity and convenience - all operations could potentially be on the same line, separated by spaces; or each operation could be on a new line in the file. More information on Script Writing, including the meaning of the command prefixes shown above, can be found in my tutorial here.
So, what does the Script do?
The Script should be run using the AutoCAD SCRIPT command in a new blank drawing. The Script will then start the OPEN command and will open the drawing with filename "C:/Drawing1.dwg" (double-quotes are only necessary if the filename contains spaces (since these would otherwise be interpreted as part of the Script), however, in my opinion, it is easier to include them every time).
The Script will then attempt to load the AutoLISP file myfunction.lsp, and will return nil if this file cannot be loaded. Note that the second optional argument for the AutoLISP load function has been supplied to ensure that the load function does not error if the AutoLISP file in question cannot be loaded.
The Script file the includes a conditional if statement testing whether the symbol myfunction evaluates to a non-nil value, i.e. whether the function myfunction is defined. (Aside: the reason that the if statement is not testing the return of the load expression is because one cannot be guaranteed that the final expression evaluated within a loaded AutoLISP file will return a non-nil value, hence it is safe to test whether the function has in fact been defined following the load).
If the function is indeed defined, the Script will evaluate the AutoLISP function to operate on the opened drawing.
Following completion of the AutoLISP program (since AutoLISP does not permit the use of multiple processor threads, the Script must wait until the AutoLISP function has completed evaluation before proceeding), the Script will then issue the QSAVE command to save the opened drawing, followed by the CLOSE command to close the open drawing and return to the blank new drawing from which the Script was initiated.
Note that there is no space following the CLOSE command, since, as noted above, the new-line also represents the user issuing Enter at the command-line, and will ensure the CLOSE command is executed.
Now, the Script will move to the next line and commence the OPEN command to process the next drawing.
Of course, this is the bare minimum requirements for this method of batch processing - there are many enhancements which may be implemented to streamline the procedure.
For example, rather than writing the Script manually, the first improvement could be to utilise an AutoLISP program to construct the Script - indeed, this is the motivation behind my Script Writer program.
A natural progression would then be to also automatically write the AutoLISP program to an AutoCAD Support File Search Path, leaving the user with one less item to worry about in the procedure.
Finally, the whole process can be wrapped up with a fancy GUI, allowing the user to indirectly tailor the AutoLISP function to be evaluated on each drawing, and with prompts for drawing selection allowing the user to indirectly tailor the generation of the Script file - these concepts are aptly demonstrated by my Batch Attribute Editor program suggested earlier.
I hope this explanation is clear & sufficiently meets your expectations.
@BlackBox_ wrote:
@Lee_Mac wrote:By using a Script file in conjunction with an AutoLISP program, one can exploit the batch processing ability of the Script whilst harnessing the superior power, control & error trapping afforded by an AutoLISP program.
... This has 'new LISP book author' written all over it; just saying.
I think I just wrote it...
Thank you for your kind words bhull 
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