已经两天了，求助！！
 

已经两天了，求助！！
www.dimcax.com
已经两天了，求助！！
(defun c:cx () ;/ a b cxm sx sx1 ；查询扩展数据
(setq a (entget (car (entsel)) '("*")))
(setq b (cdr (assoc -3 a)))
(setq cxm (car (car b)))
(setq sx1 (cdr (car b)))
(setq sx (cdr (car sx1)))
(alert (strcat "\n属性:" " " sx))
)
(defun c:xx () ；修改扩展数据
(while (not (setq a (entsel "\n选择一个实体: ")))
(alert "没选中任何实体...")
)
(setq plist (entget (car a)))
(setq v (getstring "\n属性: ")
l (cons 1000 v)
)
(regapp "sx")
(setq aaa (list (list -3 (list "sx" l))))
(setq newb (append plist aaa))
(entmod newb)
(princ)
)
(princ)
下面这一段就不行了
(defun c:aa()
(setq pt (getpoint "\n框选第一点"))
(setq spl (ssget "c" pt (getcorner pt) '((8 . "gcd") (2 . "gc
d
全是些基本操作，多看书
d
为什么
1 setq a (entget (car (entsel)) '("*")))
2 (while (not (setq a (entsel "\n选择一个实体: ")))
(alert "没选中任何实体...")
)
两种都可以
而
3 (setq pt (getpoint "\n框选第一点"))
(setq spl (ssget "c" pt (getcorner pt) '((8 . "gcd") (2 . "gc
d
(setq spl (ssget "c" pt (getcorner pt) '((cons 8 "gcd") (cons 2 "gc
d
(setq pt (getpoint "\n框选第一点"))
(setq spl (ssget "c" pt (getcorner pt) '((8 . "gcd") (2 . "gc
d