create a storage system from storing variables using ldata

I recommend looking at Peter's routine...its a good one. You can get the code at:
www.waun.org

I have started using it on a trial bases in some of my routines, works great. I
am using
autocad 2005 windows 2000

Gary


The following is from Peter Jamtgaard email:

I was pondering the storing of variable inside drawings.
I decided to try and create a storage system from storing variables using ldata.
I wouldn't recommend storing objects using objects, safearrays or variants in the
storage system.

It will cause errors during saving.

The syntax is
(savevariable 'testvariable)
(restorevariable 'testvariable)
(restorevariables)

if testvariable is a valid variable (not nil) it will store itself into the
drawing.
The restorevariable can be used during a later drawing session to get that value.
Peter Jamtgaard

;**************************************************************************
; Written By: Peter Jamtgaard copr January 2005
;**************************************************************************
;
; Save a variable into drawing for later use with its string name and value
;**************************************************************************

 

I agree. I think this is one of the best things Autodesk ever did for programmers. This facility makes my life sooooo much easier!

 

LData stinks. I hope you enjoy programming in Visual LISP forever, because
the data is not retrievable in VB(A) to the average programmer.

--
R. Robert Bell


I agree. I think this is one of the best things Autodesk ever did for
programmers. This facility makes my life sooooo much easier!

 

Robert, since you're so good at insulting people, why don't you just go do it in the VBA forum with the "average" programmers?

I didn't solicit your negative attitude, so why did you volunteer it?

With a negative outlook like that, I can only image what kind of person you must be to work with.

 

I'm not insulting you. LData has issues that most people are unaware of. I
have had to help other firms migrate their data out of LData into
traditional dictionaries so that they could continue their development in
VBA. If you search this ng over the past few years you will see that I've
warned of this issue several times.

My initial post was brief and blunt because I didn't have time at the point
to write a more detailed response, one that might not have ruffled your
feathers.

--
R. Robert Bell


Robert, since you're so good at insulting people, why don't you just go do
it in the VBA forum with the "average" programmers?

I didn't solicit your negative attitude, so why did you volunteer it?

With a negative outlook like that, I can only image what kind of person you
must be to work with.

 

OK. If I misunderstood your post, please accept my apology, Robert. Maybe look closer at what you're talking about and see if there's some potential problem that I'm not aware or.

Why couldn't I just write a translator function that's called from my (ldata) functions. Since I have one function for reading data, one for writing data and one for deleting keys, it soesn't seem like it would be that big of a deal.

Am I missing something?

Thanks for the advice.

 

You shouldn't be apologizing for anything. You didn't
misunderstand anything. Mr. Bell is the only one here
that owes the rest of the group an apology.

There's no reason whatsoever why you can't do that.

Since it is possible to migrate LDATA to other storage
mediums, the only risk you run is that Autodesk will
do what it did in the past, again (LDATA written using
R14 Vital/Visual LISP was completely inaccessable in
AutoCAD 2000, and Autodesk did nothing to mitigate
that).

 

Tony,

I don't see much difference between what Robert said, and this advice from you dated
9/9/2004.

-----------------------------------------------
You are making a big mistake by using 'LDATA' to begin with.

I would strongly advise you to use your own xrecord and dictionary code, and avoid
LDATA like the plague.
-----------------------------------------------

I'm not trying to make a point. I'm simply wondering if you've changed your mind on
this issue? I, for one, would like to know. I've avoided ldata given this type of
advice from people like you and Robert. Folks who know more about this stuff than I
ever will.

Joe Burke

 

My opinion on the use of LDATA hasn't changed, but I don't
see that as the main issue, which is:

"I hope you enjoy programming in Visual LISP forever"

Which I interpret as meaning that if you do use LDATA, you
are sentencing yourself to LISP Purgatory for eternity, with
no recourse.

Do you agree or disagree with that?

 

My point is that, if you write a VBA function, and you need to look at your
legacy data stored in LData, you are stuck with the requirement of needing
some code in Visual LISP to get to the data. If you thought you could get to
the data from VBA _only_ you are stuck. You would need to run some VLISP
code to migrate the data into "friendly" formats. So why not just start with
the non-LData formats?

--
R. Robert Bell


OK. If I misunderstood your post, please accept my apology, Robert. Maybe
look closer at what you're talking about and see if there's some potential
problem that I'm not aware or.

Why couldn't I just write a translator function that's called from my
(ldata) functions. Since I have one function for reading data, one for
writing data and one for deleting keys, it soesn't seem like it would be
that big of a deal.

Am I missing something?

Thanks for the advice.

 

Ok, I'm a beginner in Vlisp, so can someone point me in the right direction, if
Ldata is not the answer. I am looking for help in developing code to store a
varable,
I quess on layer zero (so it can't be deleted). Then retrieve that data when the
drawing is reopened. I would like the routine to be similar to Peter's with the
same type of functions: save restore and restoreall.

All this other talk about converting into VBA is not really important to me. I am
concerned about what Autodesk may do with Ldata in the future.

Any help (blunt or otherwise..I have thick skin) would be welcomed.

I use the following code but it's not Vlisp:

Code:

;;I use this program to hide my company's name, person
;;& telephone number inside the undeleted  Layer "0"
;;for Copyright purpose.
(defun C:XD-GDF  (/ APPNAME CN DATA ELIST ENT ITEM LYR N PC TABLE TP)
(setq APPNAME "DWG_OWNED_BY")
(regapp APPNAME)
(setq ITEM NIL
DATA NIL)
;;(setq CN (strcat "Employer = " (getstring "\nCompany Name: ")))
(setq CN "Company = GARY DAVIDSON FOWLER ARCHITECT")
;;(setq PC(strcat "Employee = " (getstring t "\nPerson to Contact: ")))
(setq PC (strcat "Drawn By = " (getvar "loginname")))
;;(setq TP (strcat "Phone = " (getstring "\nTelephone: ")))
(setq TP "Phone = 972.404.0182   Email = ")
(setq ITEM (cons CN (cons PC (list TP))))
(setq N 1)
(foreach
S  ITEM
(setq ELIST (set (read (strcat "X" (itoa N))) (cons 1000 S)))
(setq DATA (cons ELIST DATA))
(setq N (1+ N)))
(setq TABLE (list (list -3 (cons APPNAME DATA))))
(setq LYR (tblobjname "layer" "0"))
(setq ENT (entget LYR))
(entmod (append ENT TABLE))
(princ (setq TABLE (cdadr (assoc -3 TABLE))))
(princ))

Gary

 

Tony,

I'm not qualified to agree or disagree since my knowledge ends at VLSIP.

Regardless, thank you for the clarification.

Joe Burke

 

Migrating LDATA can only be done using Visual LISP,
it has nothing to do with other APIs or languages.