cad制图，方便制图，可以在一个图形范围内，简易控制图形输入 -　　Function C:GPath is the main program function and defines the

　　AutoCAD GPATH command.

(defun C:GPath ()

　　Ask the user for input: first for path location and

　　direction, then for path parameters. Continue only if you have

　　valid input.

(if (gp:getPointInput)　　　　

(if (gp:getDialogInput)

(progn

　　At this point, you have valid input from the user.

　　Draw the outline, storing the resulting polyline

　　"pointer" in the variable called PolylineName.

(setq PolylineName (gp:drawOutline))

(princ "\nThe gp:drawOutline function returned <")

(princ PolylineName)

(princ ">")

(Alert "Congratulations- your program is complete!")

)

(princ "\nFunction cancelled.")　　

)

(princ "\nIncomplete information to draw a boundary.")

)

(princ)　　exit quietly

)

　　Display a message to let the user know the command name.

(princ "\nType gpath to draw a garden path.")

(princ)