;Reply From: Bethel, David 
;Date: Jun/19/00 - 19:41 (GMT) 
   
;    Re: Change attribute definition inside a block

(defun c:ATAG (/ bname tdef fe ed tag tlist npmt)
(while (or (not bname)
(= bname "")
(not (tblsearch "BLOCK" bname)))
(setq bname (strcase (getstring "\nBlock Name: "))))
(setq tdef (tblsearch "BLOCK" bname))
(and (/= (logand (cdr (assoc 70 tdef)) 2) 2)
(princ "\nBlock Contains No Attributes")
(exit))
(setq fe (cdr (assoc -2 tdef)))
(while fe
(setq ed (entget fe))
(and (= (cdr (assoc 0 ed)) "ATTDEF")
(setq tlist (cons (cdr (assoc 2 ed)) tlist)))
(setq fe (entnext fe)))
(prin1 tlist)
(while (or (not tag)
(not (member tag tlist)))
(setq tag (strcase (getstring "\nTag To Change: "))))
(setq npmt (getstring T "\nNew Prompt: "))
(setq fe (cdr (assoc -2 tdef)))
(entmake tdef)
(while fe
(setq ed (entget fe))
(if (not (and (assoc 2 ed)
(= (cdr (assoc 0 ed)) "ATTDEF")
(= (cdr (assoc 2 ed)) tag)))
(entmake ed)
(entmake (subst (cons 3 npmt) (assoc 3 ed) ed)))
(setq fe (entnext fe)))
(entmake '((0 . "ENDBLK")))
(prin1))

;|

;Svend,

;This will redefine the block and change the prompt for all ATTDEFs
;with the selected name. Not tested real well. Use at your own risk!
;-David
;
;PS Jon F. will not like the use of (exit)