将生成的随机数写入图像文件
/// <summary> /// 该方法是将生成的随机数写入图像文件 /// </summary> /// <param name="VNum">VNum是一个随机数</param> public MemoryStream Create(out string VNum) { VNum = RndNum(4); Bitmap Img = null; Graphics g = null; MemoryStream ms = null; System.Random random = new Random(); //验证码颜色集合 Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple }; //验证码字体集合 string[] fonts = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" }; //定义图像的大小,生成图像的实例 Img = new Bitmap((int)VNum.Length * 18, 32); g = Graphics.FromImage(Img);//从Img对象生成新的Graphics对象 g.Clear(Color.White);//背景设为白色 //在随机位置画背景点 for (int i = 0; i < 100; i++) { int x = random.Next(Img.Width); int y = random.Next(Img.Height); g.DrawRectangle(new Pen(Color.LightGray, 0), x, y, 1, 1); } //验证码绘制在g中 for (int i = 0; i < VNum.Length; i++) { int cindex = random.Next(7);//随机颜色索引值 int findex = random.Next(5);//随机字体索引值 Font f = new System.Drawing.Font(fonts[findex], 15, System.Drawing.FontStyle.Bold);//字体 Brush b = new System.Drawing.SolidBrush(c[cindex]);//颜色 int ii = 4; if ((i + 1) % 2 == 0)//控制验证码不在同一高度 { ii = 2; } g.DrawString(VNum.Substring(i, 1), f, b, 3 + (i * 12), ii);//绘制一个验证字符 } ms = new MemoryStream();//生成内存流对象 Img.Save(ms, ImageFormat.Jpeg);//将此图像以Png图像文件的格式保存到流中 //回收资源 g.Dispose(); Img.Dispose(); return ms; }
控制器中加入方法
/// <summary> /// 验证码 /// </summary> /// <returns></returns> public FileContentResult ValidateCode() { string code = ""; System.IO.MemoryStream ms = new Models.verify_code().Create(out code); Session["gif"] = code;//验证码存储在Session中,供验证。 Response.ClearContent();//清空输出流 return File(ms.ToArray(), @"image/png"); }
js引用
<img id="imgVerify" src="/Sys/Account/ValidateCode" alt="看不清?点击更换" onclick="this.src = this.src + '?'" style="vertical-align:middle;" />
ok了。