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1 using System; 2 using System.Data; 3 using System.Configuration; 4 using System.Collections; 5 using System.Web; 6 using System.Web.Security; 7 using System.Web.UI; 8 using System.Web.UI.WebControls; 9 using System.Web.UI.WebControls.WebParts;10 using System.Web.UI.HtmlControls;11 using System.Drawing;12 13 public partial class checkcode : System.Web.UI.Page14 {15 protected void Page_Load(object sender, EventArgs e)16 {17 CreateCheckCodeImage(GenerateCheckCode());18 }19 private string GenerateCheckCode()20 {21 int number;22 char code;23 string checkCode = String.Empty;24 System.Random random = new Random();25 26 for (int i = 0; i < 4; i++)27 {28 number = random.Next();29 30 if (number % 2 == 0)31 code = (char)('0' + (char)(number % 10));32 else33 code = (char)('A' + (char)(number % 26));34 35 checkCode += code.ToString();36 }37 // 随机生成的字母或数字组合放入Cookie中，则可以通过Cookie取得验证码，查看输入的是否匹配38 Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));39 return checkCode;40 }41 private void CreateCheckCodeImage(string checkCode)42 {43 if (checkCode == null || checkCode.Trim() == String.Empty)44 return;45 System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22);46 Graphics g = Graphics.FromImage(image);47 try48 {49 //生成随机生成器50 Random random = new Random();51 //清空图片背景色52 g.Clear(Color.White);53 //画图片的背景噪音线54 for (int i = 0; i < 2; i++)55 {56 int x1 = random.Next(image.Width);57 int x2 = random.Next(image.Width);58 int y1 = random.Next(image.Height);59 int y2 = random.Next(image.Height);60 g.DrawLine(new Pen(Color.Black), x1, y1, x2, y2);61 }62 Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));63 System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), 64 Color.Blue, Color.DarkRed, 1.2f, true);65 g.DrawString(checkCode, font, brush, 2, 2);66 //画图片的前景噪音点67 for (int i = 0; i < 100; i++)68 {69 int x = random.Next(image.Width);70 int y = random.Next(image.Height);71 image.SetPixel(x, y, Color.FromArgb(random.Next()));72 }73 //画图片的边框线74 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);75 System.IO.MemoryStream ms = new System.IO.MemoryStream();76 image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);77 Response.ClearContent();78 Response.ContentType = "image/Gif";79 Response.BinaryWrite(ms.ToArray());80 }81 finally82 {83 g.Dispose();84 image.Dispose();85 }86 }87 } 2】
1 using System; 2 using System.Collections; 3 using System.Configuration; 4 using System.Data; 5 using System.Linq; 6 using System.Web; 7 using System.Web.Security; 8 using System.Web.UI; 9 using System.Web.UI.HtmlControls;10 using System.Web.UI.WebControls;11 using System.Web.UI.WebControls.WebParts;12 using System.Xml.Linq;13 using System.Drawing;14 using System.Drawing.Imaging;15 using System.Drawing.Drawing2D;16 17 namespace Web18 {19 public partial class yanzheng : System.Web.UI.Page20 {21 protected void Page_Load(object sender, EventArgs e)22 {23 CreateCheckCodeImage(GenCode(7));24 }25 /**/26 /// 27 /// '产生随机字符串28 /// 29 /// 随机出几个字符30 /// 随机出的字符串 31 private string GenCode(int num)32 {33 string[] source = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z" };34 string code = "";35 Random rd = new Random();36 int i;37 for (i = 0; i < num; i++)38 {39 code += source[rd.Next(0, source.Length)];40 }41 return code;42 43 }44 45 /**/46 /// 47 /// 生成图片（增加背景噪音线、前景噪音点）48 /// 49 /// 随机出字符串50 private void CreateCheckCodeImage(string checkCode)51 {52 if (checkCode.Trim() == "" || checkCode == null)53 return;54 Session["Code"] = checkCode; //将字符串保存到Session中，以便需要时进行验证55 System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)(checkCode.Length * 15), 22);56 Graphics g = Graphics.FromImage(image);57 try58 {59 //生成随机生成器60 Random random = new Random();61 62 //清空图片背景色63 g.Clear(Color.White);64 65 // 画图片的背景噪音线66 int i;67 for (i = 0; i < 30; i++)68 {69 int x1 = random.Next(image.Width);70 int x2 = random.Next(image.Width);71 int y1 = random.Next(image.Height);72 int y2 = random.Next(image.Height);73 g.DrawLine(new Pen(Color.Gainsboro), x1, y1, x2, y2);//绘制一条连接由坐标对指定的两个点的线条74 }75 76 Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold));77 System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.MidnightBlue, Color.Green, 1.2F, true);78 g.DrawString(checkCode, font, brush, 2, 2);79 80 //画图片的前景噪音点81 g.DrawRectangle(new Pen(Color.YellowGreen), 0, 0, image.Width - 1, image.Height - 1);82 83 //输出84 System.IO.MemoryStream ms = new System.IO.MemoryStream();85 image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);86 Response.ClearContent();87 Response.ContentType = "image/Gif";88 Response.BinaryWrite(ms.ToArray());89 90 }91 catch92 {93 g.Dispose();94 image.Dispose();95 }96 97 }98 }99 }