要求用vc写一个画直线，矩形和椭圆的程序 采用橡皮筋模式 -vc was asked to use a line drawing, rectangle and ellipse procedures used rubber-band model

这时候图形学里面用的橡皮筋直线,可以自己用键盘设计起点,用左右方向键控制直线走向-this time graphics inside the rubber-band linear, his keyboard design starting point, use the direction keys around to control line