C#画图——Graphics

　　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 }

后台

@{
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(╯▽╰ )）：