打印内容绘制类，使用该类可轻松获得当前打印机的HDC，直接在HDC上绘制图像既可，类中集成了打印机的自动检测识别。-Print the contents of drawing class, the class can be easily obtained using the current printer' s HDC, HDC to draw the image directly in the can, the class of integrated automatic detectio