Neeke’s Blog

private void GetCode()    {        //创建验证码位图，宽为500个像素，高为150个像素        Bitmap myCode = new Bitmap(500, 150);        //获取位图物理路径        string codePath = Server.MapPath("~") + "\\code.jpg";        //创建随机数        Random rd = new Random();        //验证码字符串        string line = "";        for (int j = 0; j < 6; j++)        {            //随即产生大于等于0小于3的数            int i = rd.Next(3);                        if (i == 0)            {                //若为0则生成A-Z的字符并追加到line                line += char.ConvertFromUtf32(rd.Next(65, 92));            }            else if (i == 1)            {                //若为1则生成a-z的字符串并追加到line                line += char.ConvertFromUtf32(rd.Next(97, 123));            }            else            {                //其他则生成0-9的数字并追加到line                line += rd.Next(10);            }        }        //创建Graphics对象        Graphics g = Graphics.FromImage(myCode);        //画上字符串line，且字体随机，大小为90，采用红色实线，从位图的左上角开始画        g.DrawString(line, new Font(FontFamily.Families[rd.Next(2)], 90), new SolidBrush(Color.Red), 0, 0);        //给验证码画上10条随机线条加以干扰，黄绿实线，粗度为2，起始位置，终止位置均为不超过位图大小的随机数        for (int i = 0; i < 10; i++)        {            g.DrawLine(new Pen(new SolidBrush(Color.LightGreen), 3), new Point(rd.Next(500), rd.Next(150)), new Point(rd.Next(500), rd.Next(150)));        }        //获得水印图片        System.Drawing.Image water = System.Drawing.Image.FromFile(Server.MapPath("~") + "\\water.jpg");        //将水印画至位图右下角        g.DrawImage(water, new Point(500-water.Width,150-water.Height));        //销毁Graphics        g.Dispose();        //保存验证码        myCode.Save(codePath, System.Drawing.Imaging.ImageFormat.Jpeg);        //销毁位图对象        myCode.Dispose();        //显示至网页        this.Image1.ImageUrl = "code.jpg";    }