CXATTFILLBlocks and attributesVersion 1.0.0Tested in AutoCAD

Fill an attribute in many blocks

Sets one attribute to the same value in every selected block, for example STATUS = NEW across a whole sheet, optionally only where it is still empty.

Download cxattfill.lsp LISP terms

How to use it

Type CXATTFILL and select the blocks.
Pick the attribute tag from the list shown and enter the new value (- for empty).
Choose whether to fill only the attributes that are empty.

Good to know

Blocks without that attribute are skipped.

Load it in AutoCAD

Save the file anywhere you like.
Type APPLOAD, pick the file and choose Load.
Type the command name: CXATTFILL.

To have it at every start, add it to the Startup Suite in the same dialog, or load a whole folder at once with the optional loader. About the optional loader

Tested in AutoCAD (full version). Other programs that run AutoLISP may work, but they are not tested.

The code

Plain text, nothing hidden. Copy it into a file named cxattfill.lsp, or download it.

;;; ============================================================================
;;; CXATTFILL - Fill an attribute in many blocks
;;; Version 1.0.0
;;; CADXChange LISP tools - https://cadxchange.net/resources/lisp/cxattfill
;;; Tested in: AutoCAD (full version). Other programs that run AutoLISP may work but are not tested.
;;; Copyright (c) CADXChange. Free for personal and commercial use; do not resell or
;;; republish it as a collection. Terms: https://cadxchange.net/legal/lisp-terms
;;; ============================================================================

;; Set the attribute TAG to VALUE in every block reference in NAMES that has it.
;; ONLYEMPTY = T leaves attributes that already hold a value alone. Returns how many blocks were changed.
(defun cx:attfill-run (names tag value onlyempty / n a)
  (setq n 0)
  (foreach e names
    (if (setq a (cx:att-find e tag))
      (if (or (not onlyempty) (= (cx:trim (cx:dxf 1 (entget a))) ""))
        (progn
          (cx:att-set e tag value)
          (setq n (1+ n))))))
  n)

(defun c:CXATTFILL ( / *error* cx:sv ss names tags tag value only n)
  (setq *error* cx:err)
  (if (setq ss (cx:pick "\nSelect blocks with attributes: " '((0 . "INSERT") (66 . 1))))
    (progn
      (setq names (cx:ss->list ss)
            tags  (cx:tags names))
      (if (null tags)
        (princ "\nThe selected blocks have no attributes.")
        (progn
          (princ (strcat "\nAttributes in the selection: " (cx:join tags ", ")))
          (setq tag (cx:ask-str "Attribute tag" (car tags)))
          (if (not (member (strcase tag) (mapcar 'strcase tags)))
            (princ (strcat "\nNo selected block has an attribute named " tag "."))
            (progn
              (setq value (cx:ask-str "New value (- for empty)" "")
                    only  (= (cx:ask-kw "Only where the attribute is empty" "Yes No" "No") "Yes"))
              (cx:start '(("CMDECHO" . 0)))
              (setq n (cx:attfill-run names tag value only))
              (princ (strcat "\n" (itoa n) " block(s) changed."))
              (cx:end)))))))
  (princ))


;;; ---- Shared helpers (used by the command above; identical in every CADXChange tool) ----

(defun cx:dxf (code ed)
  (cdr (assoc code ed)))

;; The ATTRIB entities of a block reference, in order.
(defun cx:attribs (ins / e out)
  (setq e (entnext ins))
  (while (and e (= (cx:dxf 0 (entget e)) "ATTRIB"))
    (setq out (cons e out) e (entnext e)))
  (reverse out))

;; The ATTRIB of a block reference with the tag TAG (any case), or nil.
(defun cx:att-find (ins tag / r)
  (foreach a (cx:attribs ins)
    (if (and (not r) (= (strcase (cx:dxf 2 (entget a))) (strcase tag))) (setq r a)))
  r)

;; Remove spaces and tabs at both ends.
(defun cx:trim (s / a b)
  (setq a 1 b (strlen s))
  (while (and (<= a b) (member (substr s a 1) '(" " "\t"))) (setq a (1+ a)))
  (while (and (>= b a) (member (substr s b 1) '(" " "\t"))) (setq b (1- b)))
  (substr s a (max 0 (1+ (- b a)))))

;; Replace the text of a TEXT, ATTRIB, ATTDEF or MTEXT.
(defun cx:text-set (ename str / ed out)
  (setq ed (entget ename))
  (if (= (cx:dxf 0 ed) "MTEXT")
    (progn
      ;; MTEXT stores text in 250-character pieces: 3 groups for the first pieces, 1 for the last
      (foreach p ed (if (not (member (car p) '(1 3))) (setq out (cons p out))))
      (setq out (reverse out))
      (while (> (strlen str) 250)
        (setq out (append out (list (cons 3 (substr str 1 250)))) str (substr str 251)))
      (setq ed (append out (list (cons 1 str)))))
    (setq ed (subst (cons 1 str) (assoc 1 ed) ed)))
  (entmod ed)
  (entupd ename)
  T)

;; Set the attribute TAG of a block reference to VALUE; returns T when the block has that attribute.
(defun cx:att-set (ins tag value / a)
  (if (setq a (cx:att-find ins tag))
    (progn (cx:text-set a value) (entupd ins) T)))

;; Close the undo step and put the system variables back.
(defun cx:end ()
  (foreach v cx:sv (setvar (car v) (cdr v)))
  (command "_.UNDO" "_End")
  (setq cx:sv nil)
  (princ))

;; Error handler: restores everything, stays quiet on Esc.
(defun cx:err (msg)
  (if (> (getvar "CMDACTIVE") 0) (command))
  (cx:end)
  (if (and msg (not (wcmatch (strcase msg) "*BREAK*,*CANCEL*,*EXIT*")))
    (princ (strcat "\nError: " msg)))
  (princ))

;; Use the objects already selected, or ask the user to select; FILTER is an ssget filter list or nil.
(defun cx:pick (msg filter / ss)
  (setq ss (if filter (ssget "_I" filter) (ssget "_I")))
  (if (null ss)
    (progn
      (princ msg)
      (setq ss (if filter (ssget filter) (ssget)))))
  ss)

;; Selection set to a list of entity names.
(defun cx:ss->list (ss / i out)
  (setq i 0)
  (if ss
    (repeat (sslength ss)
      (setq out (cons (ssname ss i) out)
            i   (1+ i))))
  (reverse out))

;; The attribute tags found in a list of block references, each once, in order of appearance.
(defun cx:tags (names / out)
  (foreach e names
    (foreach a (cx:attribs e)
      (if (not (member (strcase (cx:dxf 2 (entget a))) (mapcar 'strcase out)))
        (setq out (append out (list (cx:dxf 2 (entget a))))))))
  out)

(defun cx:join (lst delim / out)
  (setq out "")
  (foreach s lst
    (setq out (if (= out "") s (strcat out delim s))))
  (if lst out ""))

;; Ask for a string (spaces allowed) with a default; "-" means an empty string.
(defun cx:ask-str (msg def / v)
  (setq v (getstring T (strcat "\n" msg " <" def ">: ")))
  (cond ((= v "") def) ((= v "-") "") (T v)))

;; Replace every OLD in STR by NEW (case sensitive).
(defun cx:replace (str old new / n out pos)
  (setq n (strlen old) out "" pos 1)
  (if (= n 0)
    str
    (progn
      (while (<= pos (1+ (- (strlen str) n)))
        (if (= (substr str pos n) old)
          (setq out (strcat out new) pos (+ pos n))
          (setq out (strcat out (substr str pos 1)) pos (1+ pos))))
      (strcat out (substr str pos)))))

;; Ask for one of the keywords in BITS ("Yes No"), default DEF; returns the keyword.
(defun cx:ask-kw (msg bits def / v)
  (initget 0 bits)
  (setq v (getkword (strcat "\n" msg " [" (cx:replace bits " " "/") "] <" def ">: ")))
  (if v v def))

;; Save the system variables in VARS ((name . value) ...), set them, and open one undo step.
;; The caller declares cx:sv as a local so the saved values live exactly as long as the command.
(defun cx:start (vars)
  (setq cx:sv (mapcar (function (lambda (v) (cons (car v) (getvar (car v))))) vars))
  (command "_.UNDO" "_Begin")
  (foreach v vars (setvar (car v) (cdr v)))
  (princ))

(princ "\nCXATTFILL loaded. Type CXATTFILL to start.")
(princ)

Version history

Version 1.0.0 · 27 Ekim 2026

First release.

Need this across many drawings?

BlockSync does this kind of job on a whole folder of drawings in one run.

BlockSync