using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Drawing; using System.Drawing.Imaging; public partial class Admin_verify : System.Web.UI.Page { private int codelen = 4; //验证码长度 private int finenes = 85; //图片清晰度 private int imageHeight = 24;//图片高度 private int imgWidth = 48; //图片宽度 private string fontfamily = "微软雅黑"; //字体样式 private int fontsize = 14; //字体大小 private int x = 0; //x坐标 private int y = 0; //y坐标 protected void Page_Load(object sender, EventArgs e) { //验证码 string validateCode = CreateCodeVerfiy();//生成验证码 Bitmap bitmap = new Bitmap(imgWidth, imageHeight);//生成Bitmap图像 ImageBig(bitmap); //图像背景 DrewValidateCode(bitmap, validateCode);//绘制验证码图像 bitmap.Save(Response.OutputStream, ImageFormat.Jpeg);//保存图像,等待输出 } //验证码数字的生成 protected string CreateCodeVerfiy() { string code = ""; Random rd = new Random(); for (int i = 0; i < codelen; i++) { int n = rd.Next(10); //随机生成4个数字 code += n.ToString(); } Session["verify"] = code; return code; } //干扰点生成 protected void ImageBig(Bitmap bimtmp) { Random rd = new Random(); for (int i = 0; i < bimtmp.Width; i++) { for (int j = 0; j < bimtmp.Height; j++) { if (rd.Next(90) <= this.finenes) { bimtmp.SetPixel(i, j, Color.LightBlue); } } } } private void DrewValidateCode(Bitmap bitmap, string validateCode)//绘制验证码图像 { Graphics g = Graphics.FromImage(bitmap);//获取绘制器对象 Font font = new Font(fontfamily, fontsize, FontStyle.Bold);//设置绘制字体 g.DrawString(validateCode, font, Brushes.Black, x, y);//绘制验证码图像 } }