1 <%@ WebHandler Language="C#" Class="ValidateCode" %> 2  3 using System; 4 using System.Web; 5 using System.Drawing; 6 using System.IO; 7  8 public class ValidateCode : IHttpHandler { 9     10     public void ProcessRequest (HttpContext context) {11         context.Response.ContentType = "text/plain";12         //context.Response.Write("Hello World");13         Random r = new Random();14         int n = r.Next(10000,100000);15         CreateValidateGraphic(n.ToString(),context);16     }17     /// <summary>18     /// 创建验证码的图片19     /// </summary>20     /// <param name="containsPage">要输出到的page对象</param>21     /// <param name="validateNum">验证码</param>22     public void CreateValidateGraphic(string validateCode, HttpContext context)23     {24         Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length * 12.0), 22);25         Graphics g = Graphics.FromImage(image);26         try27         {28             //生成随机生成器29             Random random = new Random();30             //清空图片背景色31             g.Clear(Color.White);32             //画图片的干扰线33             for (int i = 0; i < 25; i++)34             {35                 int x1 = random.Next(image.Width);36                 int x2 = random.Next(image.Width);37                 int y1 = random.Next(image.Height);38                 int y2 = random.Next(image.Height);39                 g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);40             }41             Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));42             System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),43              Color.Blue, Color.DarkRed, 1.2f, true);44             g.DrawString(validateCode, font, brush, 3, 2);45             //画图片的前景干扰点46             for (int i = 0; i < 100; i++)47             {48                 int x = random.Next(image.Width);49                 int y = random.Next(image.Height);50                 image.SetPixel(x, y, Color.FromArgb(random.Next()));51             }52             //画图片的边框线53             g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);54             //保存图片数据55             MemoryStream stream = new MemoryStream();56             image.Save(stream, System.Drawing.Imaging.ImageFormat.Jpeg);57             //输出图片流58             context.Response.Clear();59             context.Response.ContentType = "image/jpeg";60             context.Response.BinaryWrite(stream.ToArray());61         }62         finally63         {64             g.Dispose();65             image.Dispose();66         }67     }68 69     public bool IsReusable {70         get {71             return false;72         }73     }74 75 }