artdialog 异步加载页面 生成验证码

  1 /// <summary>
  2     /// 生成验证码的类
  3     /// </summary>
  4     public class ValidateCode
  5     {
  6         public ValidateCode()
  7         {
  8         }
  9         /// <summary>
 10         /// 验证码的最大长度
 11         /// </summary>
 12         public int MaxLength
 13         {
 14             get { return 10; }
 15         }
 16         /// <summary>
 17         /// 验证码的最小长度
 18         /// </summary>
 19         public int MinLength
 20         {
 21             get { return 1; }
 22         }
 23         /// <summary>
 24         /// 生成验证码
 25         /// </summary>
 26         /// <param name="length">指定验证码的长度</param>
 27         /// <returns></returns>
 28         public string CreateValidateCode(int length)
 29         {
 30             int[] randMembers = new int[length];
 31             int[] validateNums = new int[length];
 32             string validateNumberStr = "";
 33             //生成起始序列值
 34             int seekSeek = unchecked((int)DateTime.Now.Ticks);
 35             Random seekRand = new Random(seekSeek);
 36             int beginSeek = (int)seekRand.Next(0, Int32.MaxValue - length * 10000);
 37             int[] seeks = new int[length];
 38             for (int i = 0; i < length; i++)
 39             {
 40                 beginSeek += 10000;
 41                 seeks[i] = beginSeek;
 42             }
 43             //生成随机数字
 44             for (int i = 0; i < length; i++)
 45             {
 46                 Random rand = new Random(seeks[i]);
 47                 int pownum = 1 * (int)Math.Pow(10, length);
 48                 randMembers[i] = rand.Next(pownum, Int32.MaxValue);
 49             }
 50             //抽取随机数字
 51             for (int i = 0; i < length; i++)
 52             {
 53                 string numStr = randMembers[i].ToString();
 54                 int numLength = numStr.Length;
 55                 Random rand = new Random();
 56                 int numPosition = rand.Next(0, numLength - 1);
 57                 validateNums[i] = Int32.Parse(numStr.Substring(numPosition, 1));
 58             }
 59             //生成验证码
 60             for (int i = 0; i < length; i++)
 61             {
 62                 validateNumberStr += validateNums[i].ToString();
 63             }
 64             return validateNumberStr;
 65         }
 66         /// <summary>
 67         /// 创建验证码的图片
 68         /// </summary>
 69         /// <param name="containsPage">要输出到的page对象</param>
 70         /// <param name="validateNum">验证码</param>
 71         public byte[] CreateValidateGraphic(string validateCode)
 72         {
 73             Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length * 12.0), 22);
 74             Graphics g = Graphics.FromImage(image);
 75             try
 76             {
 77                 //生成随机生成器
 78                 Random random = new Random();
 79                 //清空图片背景色
 80                 g.Clear(Color.White);
 81                 //画图片的干扰线
 82                 for (int i = 0; i < 25; i++)
 83                 {
 84                     int x1 = random.Next(image.Width);
 85                     int x2 = random.Next(image.Width);
 86                     int y1 = random.Next(image.Height);
 87                     int y2 = random.Next(image.Height);
 88                     g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
 89                 }
 90                 Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));
 91                 LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),
 92                  Color.Blue, Color.DarkRed, 1.2f, true);
 93                 g.DrawString(validateCode, font, brush, 3, 2);
 94                 //画图片的前景干扰点
 95                 for (int i = 0; i < 100; i++)
 96                 {
 97                     int x = random.Next(image.Width);
 98                     int y = random.Next(image.Height);
 99                     image.SetPixel(x, y, Color.FromArgb(random.Next()));
100                 }
101                 //画图片的边框线
102                 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
103                 //保存图片数据
104                 MemoryStream stream = new MemoryStream();
105                 image.Save(stream, ImageFormat.Jpeg);
106                 //输出图片流
107                 return stream.ToArray();
108             }
109             finally
110             {
111                 g.Dispose();
112                 image.Dispose();
113             }
114         }
115         /// <summary>
116         /// 得到验证码图片的长度
117         /// </summary>
118         /// <param name="validateNumLength">验证码的长度</param>
119         /// <returns></returns>
120         public static int GetImageWidth(int validateNumLength)
121         {
122             return (int)(validateNumLength * 12.0);
123         }
124         /// <summary>
125         /// 得到验证码的高度
126         /// </summary>
127         /// <returns></returns>
128         public static double GetImageHeight()
129         {
130             return 22.5;
131         }
132     }