CXFONTSUBClean-upVersion 1.0.0Tested in AutoCAD

Replace one font file by another in all text styles

Changes every text style that uses a given font file to use another one, then regenerates the drawing so you see the result.

Download cxfontsub.lsp LISP terms

How to use it

Type CXFONTSUB.
Enter the font file to replace, for example romans.shx.
Enter the font file to use instead, for example simplex.shx.

Good to know

Big-font settings of the changed styles are cleared.

Load it in AutoCAD

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

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 cxfontsub.lsp, or download it.

;;; ============================================================================
;;; CXFONTSUB - Replace one font file by another in all text styles
;;; Version 1.0.0
;;; CADXChange LISP tools - https://cadxchange.net/resources/lisp/cxfontsub
;;; 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
;;; ============================================================================

;; Give every text style that uses the font file FROM (case ignored) the font file TO instead.
;; A big font file of such a style is cleared. Returns the style names changed.
(defun cx:fontsub-run (from to / r out names en ed)
  (setq r (tblnext "STYLE" T))
  (while r
    (if (and (cx:dxf 3 r) (= (strcase (cx:dxf 3 r)) (strcase from)))
      (setq names (cons (cx:dxf 2 r) names)))
    (setq r (tblnext "STYLE")))
  (foreach name (reverse names)
    (setq ed (entget (tblobjname "STYLE" name)))
    (setq ed (subst (cons 3 to) (assoc 3 ed) ed))
    (if (assoc 4 ed) (setq ed (subst (cons 4 "") (assoc 4 ed) ed)))
    (entmod ed)
    (setq out (cons name out)))
  (reverse out))

(defun c:CXFONTSUB ( / *error* cx:sv from to rows)
  (setq *error* cx:err)
  (setq from (cx:ask-str "Font file to replace (for example romans.shx)" ""))
  (if (= from "")
    (princ "\nNothing to replace.")
    (progn
      (setq to (cx:ask-str "Replace it with (for example simplex.shx)" ""))
      (if (= to "")
        (princ "\nNo replacement given.")
        (progn
          (cx:start '(("CMDECHO" . 0)))
          (setq rows (cx:fontsub-run from to))
          (foreach r rows (princ (strcat "\n" r)))
          (command "_.REGENALL")
          (princ (strcat "\n" (itoa (length rows)) " text style(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)))

;; 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)))

;; 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 "\nCXFONTSUB loaded. Type CXFONTSUB to start.")
(princ)

Version history

Version 1.0.0 · 27 Ekim 2026

First release.

Need this across many drawings?

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

TextSync