update attribute with filename

Using lisp, what would be the best way to update an attribute value to the filename ??

 

;;
;; Define DXF function
;;
(defun dxf (code elist)
(cdr (assoc code elist))
); end function dxf
;;
;; Local Function to modify entities (using entmod)
;;
(defun emod ()
(if (and (/= ent nil)(/= ostr nil)(/= nstr nil))
(entmod (setq ent (subst (cons 1 nstr)(cons 1 ostr) ent)))
); end if
(princ)
); end function emod
;;
;; Get the drawing name..
(setq dwgname (strcat (getvar "dwgprefix") "\\" (getvar "dwgname")))
(prompt "\nPick the Attributed Block:")
(setq ss (ssget))
(if ss
(progn
(setq D (ssname ss 0)) ; get 1st item in ss
(setq ent (entget D)) ; entity
(setq ip (cdr (assoc 10 ent))) ; get insertion point
(setq ostr "")
(setq ent (entget (entnext (dxf -1 ent)))); extract attrib
(setq ostr (cdr (assoc 1 ent))) ; pick old Atr Value
(setq nstr dwgname) ; new Drawing name
(emod) ; change entity
); end progn
); end if
(princ)

 

Where in this program is the attribute tag ??
What tag is this program updating ?

thanks

 

Is the attribute your updating - burried in a Title-Block - not the first attribute ? If so, you need to loop through the attributes, and check for a tag name, then send that to emod. Is a little different. In this program, the 'entity' is variable 'ent', which is obtained from 'd', which is 1st entity in 'ss'.
If you want to search for the attribute tag, let me know, I can revise program to loop and find it.

Bob

 

yes, I need to search for a attribute tag.
I am creating a program to update all of our drawings, and want the drawing name to be filled out automatically in the title block. The tag is "Drawing_No".

Thanks for your help.

 

If the dwgname is not what you wanted, edit the line..
(setq dwgname (strcat (getvar "dwgprefix") (getvar "dwgname")))
..to be
(setq dwgname (substr (getvar "dwgname") 1 (- (strlen (getvar "dwgname") 4)))))
........
Bob

 

IF it doesn't find the attribute. "Drawing_No", change this to:
"DRAWING_NO".
Bob

 

Why not replace the attribute with RTEXT or a FIELD object?

 

Because our customers want attributes, plus they don't have AutoCAD 2005 yet.

 

What about adding a reactor in the title block

John coon

yet.

 

Can you supply an example of this ??

Thanks.

 

Try using RTEXT

 

I posted a rtext sample in customer files. you can also go to the express
tools & select help (enter rtext)

John Coon