[编程交流] 使用Autolisp绘制pline。

(defun C:test ( / oldcmd lst p1 p2 col )
(setq oldcmd (getvar 'cmdecho)) ; store this variable
(setq lst (list)) ; construct a empty list to store the points
(initget (+ 1 2 4)) ; disallow in the prompt: pressing enter, zero or negative value
(if
        (setq n (getint "\nInput number of points: ")) ; ask for the number of points
        (progn ; if we get the number of points, do all the stuff within the progn function
                (setvar 'cmdecho 0) ; set this variable to 0, to avoid any useless prompts
                (repeat n 
                        (if (not p1) ; check if there p1 does not exist
                                (setq p1 (getpoint "\nSpecify first point")) ; ask for p1 if it does not exist 
                                (progn
                                        (setq p1 (getpoint "\nSpecify next point" (setq p2 (last (reverse lst))))) ; to display the vector from previous point
                                        (grdraw p1 p2 (if (not col) (setq col 1) (setq col (+ col 1))) 0) ; visualize the segments, with some colors
                                )
                        )
                        (setq lst (cons p1 lst)) ; add the point to the list
                ); end of repeat, all points are stored in the list
                (command "_.pline" 
                        (foreach pt lst (command "_non" pt)) ; draw each point from the list
                ) ; draw the polyline
                (redraw) ; this is used as "regen" for the grdraw function
                (setvar 'cmdecho oldcmd) ; reset the variable
        ); end of progn
);if
(princ) ; exit silently
);defun