c# 验证码

 1     /// <summary>
 2     /// 举行左上角坐标和X、Y距离
 3     /// </summary>
 4     public class Coordinate
 5     {
 6         private int x;
 7         private int y;
 8         private int xDistance = 0;
 9         private int yDistance = 0;
10 
11         /// <summary>
12         /// X距离
13         /// </summary>
14         public int XDistance
15         {
16             get { return xDistance; }
17             set { xDistance = value; }
18         }
19 
20         /// <summary>
21         /// Y距离
22         /// </summary>
23         public int YDistance
24         {
25             get { return yDistance; }
26             set { yDistance = value; }
27         }
28 
29         /// <summary>
30         /// X点坐标
31         /// </summary>
32         public int X
33         {
34             get { return x; }
35             set { x = value; }
36         }
37 
38         /// <summary>
39         /// Y点坐标
40         /// </summary>
41         public int Y
42         {
43             get { return y; }
44             set { y = value; }
45         }
46     }

  1 /// <summary>
  2     /// 反色矩形集合生产器
  3     /// </summary>
  4     public class ReverseCoordinates
  5     {
  6         /// <summary>
  7         /// 单件模式 实例
  8         /// </summary>
  9         public static readonly ReverseCoordinates Instance = new ReverseCoordinates();
 10         /// <summary>
 11         /// 总长度
 12         /// </summary>
 13         public const int TotalLenght = 650;
 14 
 15         /// <summary>
 16         /// 总宽度
 17         /// </summary>
 18         public const int TotalHeight = 250;
 19         private List<Coordinate> list = new List<Coordinate>();
 20 
 21         private ReverseCoordinates()
 22         { }
 23 
 24 
 25         /// <summary>
 26         /// 返回要反色矩形左上角坐标的集合
 27         /// </summary>
 28         /// <returns>反色矩形左上角坐标的集合</returns>
 29         public List<Coordinate> GetList()
 30         {
 31             this.CreateList();
 32 
 33             return this.list;
 34         }
 35 
 36         /// <summary>
 37         /// 创建反色矩形左上角坐标的集合
 38         /// </summary>
 39         private void CreateList()
 40         {
 41             Random random = new Random(Guid.NewGuid().GetHashCode());
 42 
 43             //创建4个角反色矩形的长和宽
 44             int cornerXDistance = random.Next(1, Convert.ToInt32(TotalLenght / 15));
 45             int cornerYDistance = random.Next(1, Convert.ToInt32(TotalLenght / 5));
 46 
 47             this.list = new List<Coordinate>();
 48 
 49             //创建左上角反色矩形
 50             Coordinate coordinate = new Coordinate();
 51 
 52             coordinate.X = 1;
 53             coordinate.Y = 1;
 54             coordinate.XDistance = cornerXDistance;
 55             coordinate.YDistance = cornerYDistance;
 56 
 57             this.list.Add(coordinate);
 58 
 59             //创建左下角反色矩形
 60             coordinate = new Coordinate();
 61 
 62             coordinate.X = 1;
 63             coordinate.Y = TotalHeight - cornerYDistance;
 64             coordinate.XDistance = cornerXDistance;
 65             coordinate.YDistance = cornerYDistance;
 66 
 67             this.list.Add(coordinate);
 68 
 69             //创建右上角反色矩形
 70             coordinate = new Coordinate();
 71 
 72             coordinate.X = TotalLenght - cornerXDistance;
 73             coordinate.Y = 1;
 74             coordinate.XDistance = cornerXDistance;
 75             coordinate.YDistance = cornerYDistance;
 76 
 77             this.list.Add(coordinate);
 78 
 79             //创建右下角反色矩形
 80             coordinate = new Coordinate();
 81 
 82             coordinate.X = TotalLenght - cornerXDistance;
 83             coordinate.Y = TotalHeight - cornerYDistance;
 84             coordinate.XDistance = cornerXDistance;
 85             coordinate.YDistance = cornerYDistance;
 86 
 87             this.list.Add(coordinate);
 88 
 89             //创建中间大的反色矩形
 90             coordinate = new Coordinate();
 91 
 92             //得到每个字的大概大小
 93             int fontSize = Convert.ToInt32(TotalLenght / 3.3);
 94 
 95             //得到每个字大概中间的部位的X值
 96             int[] sizeArray = new int[4];
 97 
 98             sizeArray[0] = fontSize;
 99             sizeArray[1] = fontSize * 1 - fontSize;
100             sizeArray[2] = fontSize * 2 - fontSize;
101             sizeArray[3] = fontSize * 3 - fontSize;
102 
103             //随机选取中间反色矩形的X值
104             int index = random.Next(0, 3);
105 
106             //得到中间反色矩形和左上角矩形的距离
107             int beginX = sizeArray[index] - cornerXDistance;
108 
109             //如果两个矩形重叠
110             if (beginX < 0)
111             {
112                 //将负的距离变正数
113                 beginX *= -1;
114             }
115             else
116             {
117                 beginX = 0;
118             }
119 
120             //为了每次中间的反色矩形位置都不一样计算偏移值
121             int offset = random.Next(beginX, Convert.ToInt32(fontSize / 2));
122 
123             coordinate.X = sizeArray[index] + offset;
124             coordinate.Y = random.Next(1, Convert.ToInt32(TotalHeight / 2));
125             coordinate.XDistance = random.Next(Convert.ToInt32(TotalLenght / 6), Convert.ToInt32(TotalLenght / 3));
126             coordinate.YDistance = random.Next(Convert.ToInt32(TotalHeight / 2), TotalHeight - 1);
127 
128             this.list.Add(coordinate);
129         }
130 
131     }

  1     /// <summary>
  2     /// 验证码生成器
  3     /// </summary>
  4     public class ValidateCode
  5     {
  6         private string checkCode;
  7 
  8         /// <summary>
  9         /// 验证码
 10         /// </summary>
 11         public string CheckCode
 12         {
 13             get { return checkCode; }
 14             set { checkCode = value; }
 15         }
 16 
 17         public ValidateCode()
 18         {
 19             this.GenerateCheckCode();
 20         }
 21 
 22         /// <summary>
 23         /// 创建随机字符串
 24         /// </summary>
 25         private void GenerateCheckCode()
 26         {
 27             int number;
 28             char code;
 29             this.checkCode = String.Empty;
 30             Random random = new Random();
 31             for (int i = 0; i < 4; i++)
 32             {
 33                 number = random.Next();
 34                 code = (char)('0' + (char)(number % 10));
 35                 this.checkCode += code.ToString();
 36             }
 37         }
 38 
 39         /// <summary>
 40         /// 生产图片
 41         /// </summary>
 42         public void CreateCheckCodeImage()
 43         {
 44             ReverseCoordinates coordinates = ReverseCoordinates.Instance;
 45 
 46             int totalLenght = ReverseCoordinates.TotalLenght;
 47             int totalHeight = ReverseCoordinates.TotalHeight;
 48 
 49             Bitmap image = null;
 50             Graphics graphics = null;
 51             MemoryStream ms = null;
 52 
 53             try
 54             {
 55                 image = new Bitmap(totalLenght + 1, totalHeight + 1);
 56                 graphics = Graphics.FromImage(image);
 57                 ms = new MemoryStream();
 58 
 59                 //清空图片背景色
 60                 graphics.Clear(Color.White);
 61                 Font fontA = new Font("Arial", Convert.ToInt32(totalLenght / 3.3), (FontStyle.Bold | FontStyle.Italic));
 62 
 63                 Random random = new Random(Guid.NewGuid().GetHashCode());
 64                 int offset = random.Next(-5, 0);
 65 
 66                 graphics.DrawString(checkCode, fontA, Brushes.Black, offset, offset);
 67                 
 68                 Color pixel;
 69 
 70                 List<Coordinate> list = coordinates.GetList();
 71 
 72                 //逐点反色
 73                 foreach (Coordinate coordinate in list)
 74                 {
 75                     int x = coordinate.X;
 76 
 77                     for (int i = 0; i < coordinate.XDistance && x < totalLenght; i++, x++)
 78                     {
 79                         int y = coordinate.Y;
 80 
 81                         for (int j = 0; j < coordinate.YDistance && y < totalHeight; j++, y++)
 82                         {
 83                             int r, g, b;
 84                             pixel = image.GetPixel(x, y);
 85 
 86                             r = 255 - pixel.R;
 87                             g = 255 - pixel.G;
 88                             b = 255 - pixel.B;
 89 
 90                             image.SetPixel(x, y, Color.FromArgb(r, g, b));
 91                         }
 92                     }
 93                 }
 94 
 95                 //画图片的边框线
 96                 graphics.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
 97 
 98                 image.Save(ms, ImageFormat.Gif);
 99 
100                 HttpResponse httpResponse = HttpContext.Current.Response;
101                 httpResponse.ClearContent();
102                 httpResponse.Expires = 0;
103                 httpResponse.ExpiresAbsolute = DateTime.Now.AddSeconds(-1);
104                 httpResponse.ContentType = "image/Gif";
105                 httpResponse.BinaryWrite(ms.ToArray());
106             }
107             finally
108             {
109                 graphics.Dispose();
110                 image.Dispose();
111                 ms.Dispose();
112             }
113         }
114     }