急求生成图片的验证码,该怎么处理

using System;using System.Collections;using System.Configuration;using System.Data;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.HtmlControls;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Drawing;public partial class valicode : System.Web.UI.Page{     protected void Page_Load(object sender, EventArgs e)    {        HttpContext.Current.Session["CheckCode"] = RndNum(4);        CreateImages(HttpContext.Current.Session["CheckCode"].ToString());    }    /// <summary>    /// 生成验证图片    /// </summary>    /// <param name="checkCode">验证字符</param>    private void CreateImages(string checkCode)    {        int iwidth = (int)(checkCode.Length * 13);        System.Drawing.Bitmap image = new System.Drawing.Bitmap(iwidth, 23);        Graphics g = Graphics.FromImage(image);        g.Clear(Color.White);        //定义颜色        Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };        //定义字体         string[] font = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" };        Random rand = new Random();        //随机输出噪点        for (int i = 0; i < 50; i++)        {            int x = rand.Next(image.Width);            int y = rand.Next(image.Height);            g.DrawRectangle(new Pen(Color.LightGray, 0), x, y, 1, 1);        }        //输出不同字体和颜色的验证码字符        for (int i = 0; i < checkCode.Length; i++)        {            int cindex = rand.Next(7);            int findex = rand.Next(5);            Font f = new System.Drawing.Font(font[findex], 10, System.Drawing.FontStyle.Bold);            Brush b = new System.Drawing.SolidBrush(c[cindex]);            int ii = 4;            if ((i + 1) % 2 == 0)            {                ii = 2;            }            g.DrawString(checkCode.Substring(i, 1), f, b, 3 + (i * 12), ii);        }        //画一个边框        g.DrawRectangle(new Pen(Color.Black, 0), 0, 0, image.Width - 1, image.Height - 1);        //输出到浏览器        System.IO.MemoryStream ms = new System.IO.MemoryStream();        image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);        HttpContext.Current.Response.ClearContent();        //Response.ClearContent();        HttpContext.Current.Response.ContentType = "image/Jpeg";        HttpContext.Current.Response.BinaryWrite(ms.ToArray());        g.Dispose();        image.Dispose();    }    /// <summary>    /// 生成随机的字母    /// </summary>    /// <param name="VcodeNum">生成字母的个数</param>    /// <returns>string</returns>    private string RndNum(int VcodeNum)    {        string Vchar = "0,1,2,3,4,5,6,7,8,9";        string[] VcArray = Vchar.Split(',');        string VNum = ""; //由于字符串很短，就不用StringBuilder了        int temp = -1; //记录上次随机数值，尽量避免生产几个一样的随机数        //采用一个简单的算法以保证生成随机数的不同        Random rand = new Random();        for (int i = 1; i < VcodeNum + 1; i++)        {            if (temp != -1)            {                rand = new Random(i * temp * unchecked((int)DateTime.Now.Ticks));            }            int t = rand.Next(VcArray.Length);            if (temp != -1 && temp == t)            {                return RndNum(VcodeNum);            }            temp = t;            VNum += VcArray[t];        }        return VNum;    }}
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网上多的是，去搜一下就可以了
看了一下8楼的代码，也试了一下，可行的，但真不知道它为什么要将前面的行数也标记上，让我删了好久
给你一个具体过程，自己添加就可以了
1.单独添加一个aspx页面，前台不填任何内容，后台将这样的代码复制进去
C# code
using System;using System.Data;using System.Configuration;using System.Collections;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;using System.Drawing;using System.Drawing.Design;using System.Drawing.Drawing2D;using System.Drawing.Printing;using System.Drawing.Imaging;using System.IO;public partial class _Default : System.Web.UI.Page{    private string CreateCheckCodeString()    { //定义用于验证码的字符数组        char[] AllCheckCodeArray ={ '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','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'};        //定义验证码字符串        string randomcode = "";        Random rd = new Random();        //生成4位验证码字符串        for (int i = 0; i < 4; i++)            randomcode += AllCheckCodeArray[rd.Next(AllCheckCodeArray.Length)];        return randomcode;    }    //生成验证码图片    protected void Page_Load(object sender, EventArgs e)    {        //定义图片的宽度        int ImageWidth = 55;        //定义图片高度        int ImageHeigh = 22;        //定义字体，用于绘制文字        Font font = new Font("Arial", 12, FontStyle.Bold);        //定义画笔，用于绘制文字        Brush brush = new SolidBrush(Color.Black);        //定义钢笔，用于绘制干扰线        Pen pen1 = new Pen(Color.FromArgb(255, 100, 100), 0);//这里也可以直接获得一个现有的color对象如：Color.Gold.我是为了美观所以定义和下面一样        Pen pen2 = new Pen(Color.FromArgb(255, 100, 100), 0);//这里根据ARGB值定义获得了一个color对象        //创建一个图像        Bitmap BitImage = new Bitmap(ImageWidth, ImageHeigh);        //从图像获取一个绘画面        Graphics graphics = Graphics.FromImage(BitImage);        //清除整个绘图画面并用颜色填充        graphics.Clear(ColorTranslator.FromHtml("#F0F0F0"));//这里从HTML代码获取color对象        //定义文字的绘制矩形区域        RectangleF rect = new RectangleF(5, 2, ImageWidth, ImageHeigh);        //定义一个随机数对象，用于绘制干扰线        Random rand = new Random();        //生成两条横向的干扰线        for (int i = 0; i < 2; i++)        {            //定义起点            Point p1 = new Point(0, rand.Next(ImageHeigh));            //定义终点            Point p2 = new Point(ImageWidth, rand.Next(ImageHeigh));            //绘制直线            graphics.DrawLine(pen1, p1, p2);        }        //生成两条纵向的干扰线        for (int i = 0; i < 2; i++)        {            //定义起点            Point p1 = new Point(rand.Next(ImageWidth), 0);            //定义终点            Point p2 = new Point(rand.Next(ImageWidth), ImageHeigh);            //绘制直线            graphics.DrawLine(pen2, p1, p2);        }        //绘制验证码文字        graphics.DrawString(CreateCheckCodeString(), font, brush, rect);        //保存图片为gif格式        BitImage.Save(Response.OutputStream, ImageFormat.Gif);        //释放对象        graphics.Dispose();        BitImage.Dispose();    }}
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C# code
private void Page_Load(object sender, System.EventArgs e)  {   this.CreateCheckCodeImage(GenerateCheckCode());  }private string GenerateCheckCode()  {   int number;   char code;   string checkCode = String.Empty;   System.Random random = new Random();   for(int i=0; i<5; i++)   {    number = random.Next();    if(number % 2 == 0)     code = (char)('0' + (char)(number % 10));    else     code = (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<25; 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.Silver), x1, y1, x2, y2);    }    Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));    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(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();   }  }
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ASP.NET实现简单的验证码

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