新手写的画风管lisp(保存变量出问题),请指教

yugarden

(defun c:ff ( / ent str dis)
  (if (= str_s nil) (setq str_s (getvar "USERS1")))
  (setq k_lay (tblsearch "layer" "A_FG"))
  (if (null k_lay)
    (command "-layer" "n" "A_FG" "c" "7" "A_FG" "")
  )
  (command "-layer" "s" "A_FG" "")
  (setq str (getstring (strcat "\n风管宽度<" str_s ">:")))
  (if (= str "")
  (setq str str_s)
  (setvar "USERS1" str)
  (setq dis (atof str)))
  (setq ent (car (entsel)))
  (vla-offset (vlax-ename->vla-object ent) (* 0.5 dis))
  (vla-offset (vlax-ename->vla-object ent) (* -0.5 dis))
  (princ)
)

caoyin

(if (= str "")
  (setq str str_s)
  (setvar "USERS1" str)
  (setq dis (atof str)))

这一段 IF 函数的语法不对

yugarden

?不懂？

新手，能否指教一下？

caoyin

(defun c:ff ( / ent str dis)
  (cond (str_s)
        ((setq str_s (getvar "USERS1"))
         (if (not (numberp (read str_s)))
           (setq str_s "10");;比如为10,这样在系统变量 "USERS1" 为 "" 时...
         )
        )
  )
  (if (null (tblsearch "layer" "A_FG"))
    (command "_.layer" "n" "A_FG" "c" "7" "A_FG" "")
  )
  (command "_.layer" "s" "A_FG" "")
  (setq str (getstring (strcat "\n风管宽度 <" str_s ">:")))
  (if (= str "")
    (setq str str_s)
    (setq str_s (setvar "USERS1" str))
  )
  (setq dis (atof str))
  (setq ent (car (entsel)))
  (vla-offset (vlax-ename->vla-object ent) (* 0.5 dis))
  (vla-offset (vlax-ename->vla-object ent) (* -0.5 dis))
  (princ)
)

yugarden

谢谢楼上,我是新手,写的东西都还不是逻辑清楚,我再对比对比,思考思考,谢谢