测试一下

using  System; using  System.Drawing; using  System.Web; public   partial   class  Default2 : System.Web.UI.Page ... {    protected void Page_Load(object sender, EventArgs e)    ...{        this.CreateCheckCodeImage(GenerateCheckCode(6, false));     }    /**//// <summary>    /// 随机生成字符串    /// </summary>    /// <param name="codeCount">字符串个数</param>    /// <param name="isSaveCookies">是存入COOKIES中,否则存入SESSION中</param>    /// <returns></returns>    private string GenerateCheckCode(int codeCount, bool isSaveCookies)    ...{        int number;        char code;        string checkCode = String.Empty;        System.Random random = new Random();        for (int i = 0; i < codeCount; i++)        ...{            number = random.Next();            if (number % 2 == 0)                code = (char)('0' + (char)(number % 10));            else                code = (char)('A' + (char)(number % 26));            checkCode += code.ToString();        }        if (isSaveCookies)        ...{            Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));        }        else        ...{            Page.Session.Contents["CheckCode"] = checkCode;        }        return checkCode;    }    /**//// <summary>    /// 生成图片    /// </summary>    /// <param name="checkCode"></param>    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();        }    } } 生成验证码