C#生成汉字验证码1、绘制汉字验证码using System.Text; //添加引用using System.Drawing; //添加引用private object[] CreateString(int strlength){//定义一个数组存储汉字编码的组成元素string[] str = new string[16] { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };Random ran = new Random(); //定义一个随机数对象object[] bytes = new object[strlength];for (int i = 0; i < strlength; i++){//获取区位码第一位int ran1 = ran.Next(11, 14);string str1 = str[ran1].Trim();//获取区位码第二位并防止数据重复ran = new Random(ran1 * unchecked((int)DateTime.Now.Ticks) + i);int ran2;if (ran1 == 13){ran2 = ran.Next(0, 7);}else{ran2 = ran.Next(0, 16);}string str2 = str[ran2].Trim();//获取区位码第三位ran = new Random(ran2 * unchecked((int)DateTime.Now.Ticks) + i);int ran3 = ran.Next(10, 16);string str3 = str[ran3].Trim();//获取区位码第四位ran = new Random(ran3 * unchecked((int)DateTime.Now.Ticks) + i);int ran4;if (ran3 == 10){ran4 = ran.Next(1, 16);}else if (ran3 == 15){ran4 = ran.Next(0, 15);}else{ran4 = ran.Next(0, 16);}string str4 = str[ran4].Trim();//定义字节变量存储产生的随机汉字区位码byte byte1 = Convert.ToByte(str1 + str2, 16);byte byte2 = Convert.ToByte(str3 + str4, 16);byte[] stradd = new byte[] { byte1,byte2};//将产生的汉字字节放入数组bytes.SetValue(stradd, i);}return bytes;}private string GetString(int length){Encoding gb = Encoding.GetEncoding("gb2312");object[] bytes = CreateString(length);//根据汉字字节解码出中文汉字string str1 = gb.GetString((byte[])Convert.ChangeType(bytes[0], typeof(byte[])));string str2 = gb.GetString((byte[])Convert.ChangeType(bytes[1], typeof(byte[])));string str3 = gb.GetString((byte[])Convert.ChangeType(bytes[2], typeof(byte[])));string str4 = gb.GetString((byte[])Convert.ChangeType(bytes[3], typeof(byte[])));string str = str1 + str2 + str3 + str4;Response.Cookies.Add(new HttpCookie("CheckCode", str));return str;}private void GraphicsImage(int length){System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((GetString(length).Length *Graphics g = Graphics.FromImage(image); //创建画布try{//生成随机生成器Random random = new Random();//清空图片背景色g.Clear(Color.White);//画图片的背景噪音线for (int i = 0; i < 1; i++){int x1 = random.Next(image.Width);int x2 = random.Next(image.Width);int y1 = random.Next(image.Height);int y2 = random.Next(image.Height);g.DrawLine(new Pen(Color.Black), x1, y1, x2, y2);}Font font = new System.Drawing.Font("Couriew New", 12, System.Drawing.FontStyle.Bold );System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush (new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);g.DrawString(GetString(length), font, brush, 2, 2);//画图片的前景噪音点for (int i = 0; i < 50; i++){int x = random.Next(image.Width);int y = random.Next(image.Height);image.SetPixel(x, y, Color.FromArgb(random.Next()));}//画图片的边框线g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);System.IO.MemoryStream ms = new System.IO.MemoryStream();image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);Response.ClearContent();Response.ContentType = "image/Gif";Response.BinaryWrite(ms.ToArray());}catch (Exception ms)Response.Write(ms.Message);}}2、绘制字母和数字混合验证码private string GenerateCheckCode(){int number;char code;string checkCode = String.Empty;Random random = new Random();for (int i = 0; i < 4; i++){number = random.Next();if (number % 2 == 0)code = (char)('0' + (char)(number % 10));elsecode = (char)('A' + (char)(number % 26));checkCode += code.ToString();}Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));return checkCode;}private void CreateCheckCodeImage(string checkCode){if (checkCode == null || checkCode.Trim() == String.Empty)return;System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)),22);Graphics g = Graphics.FromImage(image);try{//生成随机生成器Random random = new Random();//清空图片背景色g.Clear(Color.White);//画图片的背景噪音线for (int i = 0; i < 2; i++){int x1 = random.Next(image.Width);int x2 = random.Next(image.Width);int y1 = random.Next(image.Height);int y2 = random.Next(image.Height);g.DrawLine(new Pen(Color.Black), x1, y1, x2, y2);}Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold));System.Drawing.Drawing2D.LinearGradientBrush brush = newSystem.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue,Color.DarkRed, 1.2f, true);g.DrawString(checkCode, font, brush, 2, 2);//画图片的前景噪音点for (int i = 0; i < 100; i++){int x = random.Next(image.Width);int y = random.Next(image.Height);image.SetPixel(x, y, Color.FromArgb(random.Next()));}//画图片的边框线g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);System.IO.MemoryStream ms = new System.IO.MemoryStream();image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);Response.ClearContent();Response.ContentType = "image/Gif";Response.BinaryWrite(ms.ToArray());}finally{g.Dispose();image.Dispose(); }}。