private static Pen pencolor = Pens.Red;//系统自带颜色
        private static Pen CustomizePenColor = new Pen(Color.FromArgb(0, 0, 0));//自定义RGB
        private static Brush brushcolor = Brushes.White;//系统自带颜色
        private static Brush CustomizeBrushColor = new SolidBrush(Color.FromArgb(0, 0, 0));//自定义RGB