关于生成图片验证码 - ASP.NET技术论坛

楼主

已结贴√ 问题点数：50 回复次数：8

关于生成图片验证码

大家帮我看看是哪里不对了？我对着教程一步一步写的代码一样就是不出效果。

程序代码：

using System.Drawing;                //引用命名空间
using System.Drawing.Imaging;



protected void Page_Load(object sender, EventArgs e)
    {
        string yzm = Ran();
        Response.Write(yzm);

        Session["yzm"] = yzm;  //随机数写入
        int width = 70;     //图片的长度
        int heith = 20;     //图片的高度
        string fontcolor = "White";  //字体颜色
        float fontsize = 12;    //字体的大小
        string font = "宋体";   //字体

        Bitmap img = new Bitmap(width, heith);  //一个图片框
        Graphics g = Graphics.FromImage(img);   //把图片装截入
        g.DrawString(yzm, new Font(font, fontsize), new SolidBrush(Color.FromName(fontcolor)), 10, 2);
        img.Save(Response.OutputStream, ImageFormat.Jpeg);

    }

    private static string Ran()
    {
        string RanString = "123456789";
        int i = 0;
        string a = "";
        Random Ran = new Random();
        while (i <= 3)
        {
            a += Ran.Next(RanString.Length);
            i++;
        }
        return a;


    }

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第 2 楼

得分:25

你也没说明到底是个什么问题，看看这个比较一下吧

程序代码：

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 = 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);

             ms = new ();
            image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
            Response.ClearContent();
            Response.ContentType = "image/Gif";
            Response.BinaryWrite(ms.ToArray());
        }
        finally
        {
            g.Dispose();
            image.Dispose();
        }