Seleccionar bloques por nombre o por valor de atributo

Texto sin más, nada oculto. Cópialo en un archivo llamado cxblksel.lsp o descárgalo.

;;; ============================================================================
;;; CXBLKSEL - Select all blocks of one name or attribute value
;;; Version 1.0.0
;;; CADXChange LISP tools - https://cadxchange.net/resources/lisp/cxblksel
;;; 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
;;; ============================================================================

;; Every block reference in the current layout whose block name matches NAME (wildcards allowed).
;; With TAG and VALUE, only those whose attribute TAG matches VALUE (wildcards allowed, any case).
;; Returns a selection set, or nil when nothing matches.
(defun cx:blksel-run (name tag value / ss out)
  (setq ss (ssget "X" (list '(0 . "INSERT") (cons 2 name) (cons 410 (getvar "CTAB")))))
  (if (and ss tag)
    (progn
      (setq out (ssadd))
      (foreach e (cx:ss->list ss)
        (if (and (cx:att-get e tag) (wcmatch (strcase (cx:att-get e tag)) (strcase value)))
          (ssadd e out)))
      (setq ss (if (> (sslength out) 0) out nil))))
  ss)

(defun c:CXBLKSEL ( / *error* cx:sv r name filter p tag value ss)
  (setq *error* cx:err)
  (initget "Name")
  (setq r (entsel "\nClick a block, or [Name]: "))
  (cond
    ((= r "Name") (setq name (cx:ask-str "Block name (wildcards allowed)" "-")))
    ((and r (= (cx:dxf 0 (entget (car r))) "INSERT")) (setq name (cx:dxf 2 (entget (car r)))))
    (r (princ "\nThat is not a block.")))
  (if (and name (/= name ""))
    (progn
      (setq filter (cx:ask-str "Only blocks where an attribute has a value, as TAG=value (- for all)" "-"))
      (if (and (/= filter "-") (/= filter "") (setq p (cx:find filter "=" 1)))
        (setq tag   (cx:trim (substr filter 1 (1- p)))
              value (cx:trim (substr filter (1+ p)))))
      (if (setq ss (cx:blksel-run name tag value))
        (progn
          (sssetfirst nil ss)
          (princ (strcat "\n" (itoa (sslength ss)) " block(s) selected.")))
        (princ "\nNo matching blocks in this layout."))))
  (princ))


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

;; 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))

(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)

(defun cx:att-get (ins tag / a)
  (if (setq a (cx:att-find ins tag)) (cx:dxf 1 (entget a))))

;; 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))

;; 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)))

;; 1-based position of SUB in STR at or after START, or nil.
(defun cx:find (str sub start / n i r)
  (setq n (strlen sub) i start r nil)
  (if (> n 0)
    (while (and (not r) (<= i (1+ (- (strlen str) n))))
      (if (= (substr str i n) sub) (setq r i))
      (setq i (1+ i))))
  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)))))

(princ "\nCXBLKSEL loaded. Type CXBLKSEL to start.")
(princ)

Más comandos: Bloques y atributos

• CXATTFILLRellenar un atributo en muchos bloques
• CXATTNUMNumerar en secuencia un atributo de bloque
• CXATTCOPYCopiar los valores de atributos de un bloque a otros
• CXATTVISMostrar u ocultar los atributos de bloques
• CXBLKCOUNTContar bloques por nombre
• CXBLKREPLReemplazar bloques por otro bloque
• CXBLKRENRenombrar bloques en lote
• CXBLKXPDescomponer bloques conservando el texto de los atributos
• CXBLKATInsertar un bloque en muchos puntos a la vez