/// <summary>     /// PicHandler1 的摘要说明     /// </summary>     public class PicHandler1 : IHttpHandler, IRequiresSessionState     {         private string mCheckNo = string.Empty;         protected ImgBuilder _ImgBuilder = new ImgBuilder();         protected VryImgGen _ImgBuilderNew = new VryImgGen();         private string _text = string.Empty;         private string _font = "宋体";         private int _fontSize = 8;         private int _padding = 2;         public void ProcessRequest(HttpContext context)         {             mCheckNo = DisCheckNo();             context.Session["CheckCode"] = mCheckNo;             this._ImgBuilder.FontSize = this._fontSize;             this._ImgBuilder.Padding = this._padding;             if (!string.IsNullOrEmpty(this._font))             {                 this._ImgBuilder.Fonts = new string[] { this._font };             }             this._ImgBuilderNew.ChaosWight = 40;             this._ImgBuilderNew.FontSize = 25;             this._ImgBuilderNew.Padding = 3;             System.Drawing.Bitmap image =              this._ImgBuilderNew.CreateImage(mCheckNo);             System.IO.MemoryStream ms = new System.IO.MemoryStream();             image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);             context.Response.ClearContent();             context.Response.ContentType = "image/Jpeg";             context.Response.BinaryWrite(ms.ToArray());             context.Session["CheckCode"] = mCheckNo.ToString(); //如果没有实现IRequiresSessionState，则这里会出错，也无法生成图片             context.Response.End();         }         //验证码生成         protected string DisCheckNo()         {             string hash = HashCode.GetNext();             string CheckNo = string.Empty;             Random rd = new Random(DateTime.Now.Millisecond);             for (int i = 0; i < 6; i++)             {                 CheckNo += hash.Substring(rd.Next(1, hash.Length - 1), 1);             }             CheckNo = CheckNo.Replace("0", rd.Next(1, 9).ToString());             CheckNo = CheckNo.Replace("o", rd.Next(1, 9).ToString());             CheckNo = CheckNo.Replace("O", rd.Next(1, 9).ToString());             return CheckNo;         }         public bool IsReusable         {             get             {                 return false;             }         }     }

using System; using System.Drawing; using System.Text; /// <summary> /// VryImgGen 的摘要说明 /// </summary> public class VryImgGen {     public static string ChineseChars = String.Empty;     /// <summary>     /// 英文与数字串     /// </summary>     protected static readonly string EnglishOrNumChars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";     public VryImgGen()     {         rnd = new Random(unchecked((int)DateTime.Now.Ticks));     }     /// <summary>     /// 全局随机数生成器     /// </summary>     private Random rnd;     int length = 5;     /// <summary>     /// 验证码长度(默认6个验证码的长度)     /// </summary>     public int Length     {         get { return length; }         set { length = value; }     }     int fontSize = 20;     /// <summary>     /// 验证码字体大小(为了显示扭曲效果，默认30像素，可以自行修改)     /// </summary>     public int FontSize     {         get { return fontSize; }         set { fontSize = value; }     }     int padding = 4;     /// <summary>     /// 边框补(默认4像素)     /// </summary>     public int Padding     {         get { return padding; }         set { padding = value; }     }     bool chaos = true;     /// <summary>     /// 是否输出燥点(默认输出)     /// </summary>     public bool Chaos     {         get { return chaos; }         set { chaos = value; }     }     Color chaosColor = Color.LightGray;     /// <summary>     /// 输出燥点的颜色(默认灰色)     /// </summary>     public Color ChaosColor     {         get { return chaosColor; }         set { chaosColor = value; }     }     int chaosWight = 1;     /// <summary>     /// 输出燥点的浓度     /// </summary>     public int ChaosWight     {         get { return chaosWight; }         set { chaosWight = value; }     }     Color backgroundColor = Color.White;     /// <summary>     /// 自定义背景色(默认白色)     /// </summary>     public Color BackgroundColor     {         get { return backgroundColor; }         set { backgroundColor = value; }     }     Color[] colors = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };     /// <summary>     /// 自定义随机颜色数组     /// </summary>     public Color[] Colors     {         get { return colors; }         set { colors = value; }     }     string[] fonts = { "Arial", "Georgia" };     /// <summary>     /// 自定义字体数组     /// </summary>     public string[] Fonts     {         get { return fonts; }         set { fonts = value; }     }     #region 产生波形滤镜效果     private const double PI = 3.1415926535897932384626433832795;     private const double PI2 = 6.283185307179586476925286766559;     /// <summary>     /// 正弦曲线Wave扭曲图片（Edit By 51aspx.com）     /// </summary>     /// <param name="srcBmp">图片路径</param>     /// <param name="bXDir">如果扭曲则选择为True</param>     /// <param name="nMultValue">波形的幅度倍数，越大扭曲的程度越高，一般为3</param>     /// <param name="dPhase">波形的起始相位，取值区间[0-2*PI)</param>     /// <returns></returns>     public System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase)     {         System.Drawing.Bitmap destBmp = new Bitmap(srcBmp.Width, srcBmp.Height);         // 将位图背景填充为白色         System.Drawing.Graphics graph = System.Drawing.Graphics.FromImage(destBmp);         graph.FillRectangle(new SolidBrush(System.Drawing.Color.White), 0, 0, destBmp.Width, destBmp.Height);         graph.Dispose();         double dBaseAxisLen = bXDir ? (double)destBmp.Height : (double)destBmp.Width;         for (int i = 0; i < destBmp.Width; i++)         {             for (int j = 0; j < destBmp.Height; j++)             {                 double dx = 0;                 dx = bXDir ? (PI2 * (double)j) / dBaseAxisLen : (PI2 * (double)i) / dBaseAxisLen;                 dx += dPhase;                 double dy = Math.Sin(dx);                 // 取得当前点的颜色                 int nOldX = 0, nOldY = 0;                 nOldX = bXDir ? i + (int)(dy * dMultValue) : i;                 nOldY = bXDir ? j : j + (int)(dy * dMultValue);                 System.Drawing.Color color = srcBmp.GetPixel(i, j);                 if (nOldX >= 0 && nOldX < destBmp.Width                  && nOldY >= 0 && nOldY < destBmp.Height)                 {                     destBmp.SetPixel(nOldX, nOldY, color);                 }             }         }         return destBmp;     }       #endregion     /// <summary>     /// 生成校验码图片     /// </summary>     /// <param name="code">验证码</param>     /// <returns></returns>     public Bitmap CreateImage(string code)     {         int fSize = FontSize;         int fWidth = fSize + Padding;         int imageWidth = (int)(code.Length * fWidth) + 4 + Padding * 2;         int imageHeight = fSize * 2 + Padding * 2;         System.Drawing.Bitmap image = new System.Drawing.Bitmap(imageWidth - 10, imageHeight - 10);         Graphics g = Graphics.FromImage(image);         g.Clear(BackgroundColor);         //给背景添加随机生成的燥点         if (this.Chaos)         {             Pen pen = new Pen(ChaosColor, 0);             int c = ChaosWight * 10;             for (int i = 0; i < c; i++)             {                 int x = rnd.Next(image.Width);                 int y = rnd.Next(image.Height);                 g.DrawRectangle(pen, x, y, 1, 1);             }         }         int left = 0, top = 0, top1 = 1, top2 = 1;         int n1 = (imageHeight - FontSize - Padding * 2);         int n2 = n1 / 4;         top1 = n2;         top2 = n2 * 2;         Font f;         Brush b;         int cindex, findex;         //随机字体和颜色的验证码字符         for (int i = 0; i < code.Length; i++)         {             cindex = rnd.Next(Colors.Length - 1);             findex = rnd.Next(Fonts.Length - 1);             f = new System.Drawing.Font(Fonts[findex], fSize, System.Drawing.FontStyle.Bold);             b = new System.Drawing.SolidBrush(Colors[cindex]);             if (i % 2 == 1)             {                 top = top2;             }             else             {                 top = top1;             }             left = i * fWidth;             g.DrawString(code.Substring(i, 1), f, b, left, top);         }         //画一个边框 边框颜色为Color.Gainsboro         g.DrawRectangle(new Pen(Color.Gainsboro, 0), 0, 0, image.Width - 1, image.Height - 1);         g.Dispose();         //产生波形（Add By 51aspx.com）         image = TwistImage(image, true, 8, 4);         return image;     }     /// <summary>     /// 生成随机字符码     /// </summary>     /// <param name="codeLen">字符串长度</param>     /// <param name="zhCharsCount">中文字符数</param>     /// <returns></returns>     public string CreateVerifyCode(int codeLen, int zhCharsCount)     {         char[] chs = new char[codeLen];         int index;         for (int i = 0; i < zhCharsCount; i++)         {             index = rnd.Next(0, codeLen);             if (chs[index] == '\0')                 chs[index] = CreateZhChar();             else                 --i;         }         for (int i = 0; i < codeLen; i++)         {             if (chs[i] == '\0')                 chs[i] = CreateEnOrNumChar();         }         return new string(chs, 0, chs.Length);     }     /// <summary>     /// 生成默认长度5的随机字符码     /// </summary>     /// <returns></returns>     public string CreateVerifyCode()     {         return CreateVerifyCode(Length, 0);     }     /// <summary>     /// 生成英文或数字字符     /// </summary>     /// <returns></returns>     protected char CreateEnOrNumChar()     {         return EnglishOrNumChars[rnd.Next(0, EnglishOrNumChars.Length)];     }     /// <summary>     /// 生成汉字字符     /// </summary>     /// <returns></returns>     protected char CreateZhChar()     {         //若提供了汉字集，查询汉字集选取汉字         if (ChineseChars.Length > 0)         {             return ChineseChars[rnd.Next(0, ChineseChars.Length)];         }         //若没有提供汉字集，则根据《GB2312简体中文编码表》编码规则构造汉字         else         {             byte[] bytes = new byte[2];             //第一个字节值在0xb0, 0xf7之间             bytes[0] = (byte)rnd.Next(0xb0, 0xf8);             //第二个字节值在0xa1, 0xfe之间             bytes[1] = (byte)rnd.Next(0xa1, 0xff);             //根据汉字编码的字节数组解码出中文汉字             string str1 = Encoding.GetEncoding("gb2312").GetString(bytes);             return str1[0];         }     } }