(setq bn_txt nil)
(defun C:bny( / pt1 blname elast Newly_Created_Ent Obj_SS all_min all_max LL UR UL pt1);;;put temp variables
(defun Last_Entity ( / Ent_Name Last_Ent)
  (and
(setq Last_Ent (entlast))
(while (setq Ent_Name (entnext Last_Ent))
  (setq Last_Ent Ent_Name)
)
  )
  Last_Ent
)
(defun Ent_Created_by_Last_Command (Ent_Name / Ent_Next SS_Set)
  (cond
( (not Ent_Name) (ssget "_X") )
( (setq Ent_Next (entnext Ent_Name))
  (setq SS_Set (ssadd Ent_Next))
  (while (setq Ent_Next (entnext Ent_Next))
(if (entget Ent_Next) (ssadd Ent_Next SS_Set))
  )
  SS_Set
)
  )
)
(if (null bn_txt)
(progn
(setvar "TEXTSIZE" (getdist "\Height of text label (uses default style): "))
(setq bn_txt "sizeset")
)
)
(princ "\nAdd block name to drawing.")
(setq blname (vla-get-Effectivename (vlax-ename->vla-object (setq ent (car (entsel "\nSelect Block:"))))))
(vlax-invoke (vlax-ename->vla-object ent) 'copy)
(setq elast (Last_Entity))
(command "explode" (entlast))
(setq Newly_Created_Ent (ssadd))
(setq Newly_Created_Ent (Ent_Created_by_Last_Command elast))
(setq Obj_SS (ssadd))
(foreach Ent (vl-remove-if 'listp (mapcar 'cadr (ssnamex Newly_Created_Ent)))
(if (not (wcmatch (vla-get-objectname (vlax-ename->vla-object Ent)) "*MText")) (ssadd Ent Obj_SS))
)
(setq all_min '() all_max '())
(foreach ent (mapcar 'vlax-ename->vla-object (vl-remove-if 'listp (mapcar 'cadr (ssnamex Obj_SS))))
(vla-GetBoundingBox ent 'minpt 'maxpt)
(Setq all_min (cons (trans (vlax-safearray->list minpt) 1 0) all_min))
(Setq all_max (cons (trans (vlax-safearray->list maxpt) 1 0) all_max))
)
(setq LL (list (car (vl-sort (mapcar 'car all_min) '<))
   (car (vl-sort (mapcar 'cadr all_min) '<))
)
)
(setq UR (list (last (vl-sort (mapcar 'car all_max) '<))
   (last (vl-sort (mapcar 'cadr all_max) '<))
)
)
(setq UL (list (car LL) (cadr UR)))
(command "_.erase" Newly_Created_Ent "")
(setq pt1 (getpoint"\nSelect center point for block title:"))
(command "text" "c" pt1 "" "0" (strcat blname " / "  (rtos (distance UL UR) 2 1) "x" (rtos (distance LL UL) 2 1)))
(princ)
)
(princ "\nType BN to execute.")