记录两个验证码代码

代码一：

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;  
  
public partial class Test1 : System.Web.UI.Page  
{  
    protected void Page_Load(object sender, EventArgs e)  
    {  
        if (!this.IsPostBack)  
        {  
            //生成验证码   
            string temp = this.GetCode(4);  
            HttpCookie cookie = new HttpCookie("yzm");  
            cookie.Value = temp;  
            Response.Cookies.Add(cookie);  
            //画图   
            this.GetCheckCodeImage(temp);  
        }  
    }  
  
    //产生随机字符串    
    private string GetCode(int num)  
    {  
        string[] source ={ "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"};  
        string code = "";  
        Random rd = new Random();  
        for (int i = 0; i < num; i++)  
        {  
            code += source[rd.Next(0, source.Length)];  
        }  
        Session["ValidateCode"] = code;//将字符串保存到Session中，以便需要时进行验证     
        return code;  
  
    }  
 
 
    #region    验证码   
  
    /// <summary>   
    /// 生成验证码   
    /// </summary>   
    /// <param name="checkCode"></param>
    private void GetCheckCodeImage(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)),25);  
        Graphics g = Graphics.FromImage(image);  
        try  
        {  
            Random random = new Random();     //生成随机生成器    
            g.Clear(Color.White);            //清空图片背景色   
            for (int i = 0; i < 5; i++)     //画图片的背景噪音线   
            {  
                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 < 60; 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();  
        }  
    }  
 
    #endregion   
  
 
}  

代码二：

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.Imaging;
using System.IO;

public partial class viewImg : System.Web.UI.Page
{
 protected void Page_Load(object sender, EventArgs e)
    {
        string chkCode = string.Empty;

        //颜色列表，用于验证码、噪线、噪点
        Color[] color ={ Color.Black, Color.Red, Color.Blue, Color.Green, Color.Orange,

        Color.Brown, Color.DarkBlue };

        //字体列表，用于验证码
        //string[] font ={ "Times New Roman", "Arial Black", "Elephant", "Verdana", "Georgia", "Impact" };
        string[] font ={"Arial Black"};

        //验证码的字符集，去掉了一些容易混淆的字符
        char[] character ={'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' };

        Random rnd = new Random();

        //生成验证码字符串
        for (int i = 0; i < 4; i++)
        {
            chkCode += character[rnd.Next(character.Length)];
        }

        //保存验证码的Cookie
        HttpCookie anycookie = new HttpCookie("validateCookie");

        anycookie.Values.Add("ChkCode", chkCode);

        HttpContext.Current.Response.Cookies["validateCookie"].Values["ChkCode"] = chkCode;

        Bitmap bmp = new Bitmap(57, 23);

        Graphics g = Graphics.FromImage(bmp);

        g.Clear(Color.White);
          
        //画噪线
        for (int i = 0; i < 5; i++)
        {
            int x1 = rnd.Next(150);
            int y1 = rnd.Next(30);
            int x2 = rnd.Next(150);
            int y2 = rnd.Next(30);
            Color clr = color[rnd.Next(color.Length)];
            g.DrawLine(new Pen(clr), x1, y1, x2, y2);
        }
        //画验证码字符串
        for (int i = 0; i < chkCode.Length; i++)
        {
            string fnt = font[rnd.Next(font.Length)];
            Font ft = new Font(fnt, 12);
            Color clr = color[rnd.Next(color.Length)];
            g.DrawString(chkCode[i].ToString(), ft, new SolidBrush(clr), (float)i * 12, (float)3);
        }

        //画噪点
        for (int i = 0; i < 100; i++)
        {
            int x = rnd.Next(bmp.Width);
            int y = rnd.Next(bmp.Height);
            Color clr = color[rnd.Next(color.Length)];
            bmp.SetPixel(x, y, clr);
        }
        //清除该页输出缓存，设置该页无缓存
        Response.Buffer = true;

        Response.ExpiresAbsolute = System.DateTime.Now.AddMilliseconds(0);

        Response.Expires = 0;
        Response.CacheControl = "no-cache";

        Response.AppendHeader("Pragma", "No-Cache");

        //将验证码图片写入内存流，并将其以"image/Png" 格式输出
        MemoryStream ms = new MemoryStream();

        try
        {
            bmp.Save(ms, ImageFormat.Png);
            Response.ClearContent();
            Response.ContentType = "image/Png";
            Response.BinaryWrite(ms.ToArray());
        }
        finally
        {
            //显式释放资源
            bmp.Dispose();
            g.Dispose();
        }
    }
}