C#要实现简单的画图功能可以利用Graphics这个类，要使用Graphics必需using命名空间System.Drawing（此名明空间下都是关于图形的操作）。首先创建画布：
Bitmap bmp = new Bitmap(1000, 800); Graphics g = Graphics.FromImage(bmp);
清除画布的背景色，并且指定颜色填充：
g.Clear(Color.White);
开始画图：
//画矩形 g.DrawRectangle(new Pen(Color.Red), new Rectangle(0, 0, 600, 400)); //填充扇形 g.FillPie(new SolidBrush(Color.Red), new Rectangle(100, 80, 200, 200), 0, 100); //在画布上写文字 g.DrawString("A", new Font("Times New Roman", 16), new SolidBrush(Color.Black), 250, 210);
下面给出完整代码：
1 public class GraphicsController : Controller 2 { 3 public ActionResult Index() 4 { 5 return View(); 6 } 7 [HttpGet] 8 public ActionResult CreateGraphics() 9 { 10 Bitmap bmp = new Bitmap(1000, 800); 11 //画布 12 Graphics g = Graphics.FromImage(bmp); 13 //清除画布背景色，并填充指定色 14 g.Clear(Color.White); 15 //画矩形 16 g.DrawRectangle(new Pen(Color.Red), new Rectangle(0, 0, 600, 400)); 17 //画刷 18 Brush bs = new SolidBrush(Color.Blue); 19 //填充扇形 20 g.FillPie(new SolidBrush(Color.Red), new Rectangle(100, 80, 200, 200), 0, 100); 21 g.FillPie(bs, new Rectangle(100, 80, 200, 200), 100, 100); 22 g.DrawPie(new Pen(bs), new Rectangle(100, 80, 200, 200), 200, 100);//画扇形 23 g.FillPie(new SolidBrush(Color.HotPink), new Rectangle(100, 80, 200, 200), 300, 60); 24 g.DrawString("A", new Font("Times New Roman", 16), new SolidBrush(Color.Black), 250, 210); 25 //抗锯齿 26 g.SmoothingMode = SmoothingMode.AntiAlias; 27 MemoryStream ms = new MemoryStream(); 28 try 29 { 30 bmp.Save(ms, ImageFormat.Gif); 31 return File(ms.ToArray(), @"image/Gif"); 32 } 33 catch (Exception) 34 { 35 return null; 36 } 37 } 38 }
@{
Layout = null;
}
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>Index</title>
</head>
<body>
<div>
<img src="/Bitmap/CreateGraphics" width="1000" height="800" />
</div>
</body>
</html>
效果图（好像有点简陋(╯▽╰ )）：
最后推荐一些前辈的总结（比我强太多了）：
http://www.cnblogs.com/Jerry-Chou/archive/2012/03/20/2408064.html
http://www.cnblogs.com/Jerry-Chou/archive/2012/03/21/2409590.html
http://www.cnblogs.com/beyond0309/archive/2008/04/15/1155003.html验证码也可以用这种方式生成