CXLAYMRGLayersVersion 1.0.0Tested in AutoCAD

Merge layers into one and delete the rest

Moves everything from the layers of the objects you select onto the layer of one more object you click, then deletes the emptied layers.

Download cxlaymrg.lsp LISP terms

How to use it

Type CXLAYMRG and select objects on the layers to merge away.
Click an object on the layer to merge into.
Everything moves, and the empty layers are removed.

Good to know

Layer 0, Defpoints, the target and the current layer are never deleted.

Load it in AutoCAD

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

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 cxlaymrg.lsp, or download it.

;;; ============================================================================
;;; CXLAYMRG - Merge layers into one and delete the rest
;;; Version 1.0.0
;;; CADXChange LISP tools - https://cadxchange.net/resources/lisp/cxlaymrg
;;; 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
;;; ============================================================================

;; Move everything on the layers in FROM to layer TO, in model space and in the layouts, then delete the
;; emptied layers. Layer 0, Defpoints, the target and the current layer are never deleted.
;; Returns (objects-moved layers-deleted).
(defun cx:laymrg-run (from to / moved deleted ss i ed)
  (setq moved 0 deleted 0)
  (foreach name from
    (if (and (/= (strcase name) (strcase to)) (setq ss (ssget "X" (list (cons 8 name)))))
      (progn
        (setq i 0)
        (repeat (sslength ss)
          (setq ed (entget (ssname ss i)))
          (entmod (subst (cons 8 to) (assoc 8 ed) ed))
          (setq moved (1+ moved) i (1+ i))))))
  (foreach name from
    (if (and (/= (strcase name) (strcase to))
             (/= name "0")
             (/= (strcase name) "DEFPOINTS")
             (/= (strcase name) (strcase (getvar "CLAYER"))))
      (progn
        (command "_.-PURGE" "_LA" name "_N")
        (if (not (tblsearch "LAYER" name)) (setq deleted (1+ deleted))))))
  (list moved deleted))

(defun c:CXLAYMRG ( / *error* cx:sv ss src to r)
  (setq *error* cx:err)
  (if (setq ss (cx:pick "\nSelect objects on the layers to merge away: " nil))
    (if (setq src (car (entsel "\nSelect an object on the layer to merge into: ")))
      (progn
        (setq to (cdr (assoc 8 (entget src))))
        (cx:start '(("CMDECHO" . 0)))
        (setq r (cx:laymrg-run (cx:layers-of (cx:ss->list ss)) to))
        (princ (strcat "\n" (itoa (car r)) " object(s) moved to " to ", " (itoa (cadr r)) " layer(s) deleted."))
        (cx:end))))
  (princ))


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

;; 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)

;; 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))

;; The distinct layer names used by the entities in NAMES, in order of first use.
(defun cx:layers-of (names / out l)
  (foreach e names
    (setq l (cdr (assoc 8 (entget e))))
    (if (not (member l out)) (setq out (cons l out))))
  (reverse out))

;; 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))

(princ "\nCXLAYMRG loaded. Type CXLAYMRG to start.")
(princ)

Version history

Version 1.0.0 · 27 de outubro de 2026

First release.

Need this across many drawings?

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

LayerSync