c#简单绘画操作

一、要绘画就要有画布，如果我们是在PictureBox上画画的话，可以这样声明画布

Graphics g = Graphics.FromImage(this.pictureBox1.Image);

如果是在panel中绘画的话，可以这样写

Graphic g = this.panel1.CreateGraphics();

有了画布，一切就可以开始了，通过调用这个Graphics对象的各种方法，可以画出所有的图形。

二、如果我们要画一些直线或斜线的话，这些线不光滑可就不好看了，下面的语句可以达到我们的要求

g.SmoothingMode = SmoothingMode.AntiAlias;

三、画菱形

要先定义好菱形的4个点的坐标，通常顺时针依次写好就行了。然后就可以画了

Point[] p = new Point[4]; p[0] = new Point(820, 380); p[1] = new Point(835, 370); p[2] = new Point(850, 380); p[3] = new Point(835, 390); g.DrawPolygon(pen, p); 

四、填充

(1) 可以在指定的起点和范围内填充指定的颜色

g.FillRectangle(Brushes.Black, 100, 100, 50, 100);

这句代码在坐标(100,100)处填充横向50，纵向100的黑色块

(2) 填充指定多边形

比如填充菱形

先定义菱形的坐标，然后就可以填充了

Point[] p = new Point[4]; p[0] = new Point(820, 380); p[1] = new Point(835, 370); p[2] = new Point(850, 380); p[3] = new Point(835, 390); GraphicsPath gp = new GraphicsPath(); gp.AddLines(p1); Brush b = new SolidBrush(color); g.FillPath(b, gp);

五、画箭头

/// <summary> /// 在制定位置画箭头 /// </summary> /// <param name="newG">绘图图面</param> /// <param name="p">画笔</param> /// <param name="basePoint">基准点</param> /// <param name="w">底线长度的一半</param> /// <param name="h">箭头的高度</param> /// <param name="direction">方向：1，表示x；2表示y</param> private static void DrawArrow(Graphics g, Pen p, Point basePoint, int w, int h, int direction) { Point[] pt; if (direction == 1) { pt = new Point[3] { new Point(basePoint.X, basePoint.Y - 6), new Point(basePoint.X - 2, basePoint.Y), new Point(basePoint.X + 2, basePoint.Y) }; } else { pt = new Point[3] { new Point(basePoint.X + h, basePoint.Y), new Point(basePoint.X, basePoint.Y - w), new Point(basePoint.X, basePoint.Y + w) }; } g.DrawPolygon(Pens.Blue, pt); }