C# 比较不错的通用验证码

 
1 using System;
 2 using System.Collections.Generic;
 3 using System.Drawing;
 4 using System.Drawing.Imaging;
 5 using System.IO;
 6 using System.Linq;
 7 using System.Web;
 8 
 9 namespace CasCall
10 {
11     public class service_code : System.Web.UI.Page  
12     {
13         #region
14         public string RandCode()
15         {
16             int CodeCount = 4;//生成4个随机数  
17             string randomChar = "2,3,4,5,6,7,8,9,A,B,C,D,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,U,V,W,X,Y,Z";
18             randomChar = randomChar.Replace(",", "");
19             string RandomCode = "";
20             System.Threading.Thread.Sleep(3);
21             char[] allCharArray = randomChar.ToCharArray();
22             int n = allCharArray.Length;
23             System.Random random = new Random(~unchecked((int)DateTime.Now.Ticks));
24             for (int i = 0; i < CodeCount; i++)
25             {
26                 int rnd = random.Next(0, n);
27                 RandomCode += allCharArray[rnd];
28             }
29             return RandomCode;
30         }
31         #endregion
32         #region 验证码
33         ///  <summary>  
34         ///  创建验证码图片  
35         ///  </summary>  
36         ///  <param  name="randomcode">验证码</param>  
37         public byte[] CreateImage(string randomcode)
38         {
39             int randAngle = 40; //随机转动角度  
40             int mapwidth = (int)(randomcode.Length * 18);
41             Bitmap map = new Bitmap(mapwidth, 24);//创建图片背景  
42             Graphics graph = Graphics.FromImage(map);
43             graph.Clear(Color.White);//清除画面，填充背景  
44             //graph.DrawRectangle(new Pen(Color.Silver, 0), 0, 0, map.Width - 1, map.Height - 1);//画一个边框  
45 
46             Random rand = new Random();
47 
48             //验证码旋转，防止机器识别  
49             char[] chars = randomcode.ToCharArray();//拆散字符串成单字符数组  
50             //文字距中  
51             StringFormat format = new StringFormat(StringFormatFlags.NoClip);
52             format.Alignment = StringAlignment.Center;
53             format.LineAlignment = StringAlignment.Center;
54             //定义颜色  
55             Color[] c = { Color.Black, Color.Red, Color.Blue, Color.Green,   
56                             Color.Orange, Color.Brown, Color.DarkBlue };
57 
58             //画图片的背景噪音线  
59             for (int i = 0; i < 2; i++)
60             {
61                 int x1 = rand.Next(10);
62                 int x2 = rand.Next(map.Width - 10, map.Width);
63                 int y1 = rand.Next(map.Height);
64                 int y2 = rand.Next(map.Height);
65 
66                 graph.DrawLine(new Pen(c[rand.Next(7)]), x1, y1, x2, y2);
67             }
68 
69             for (int i = 0; i < chars.Length; i++)
70             {
71                 int cindex = rand.Next(7);
72                 int findex = rand.Next(5);
73                 Font f = new System.Drawing.Font("Arial", 18, System.Drawing.FontStyle.Regular);//字体样式(参数2为字体大小)  
74                 Brush b = new System.Drawing.SolidBrush(c[cindex]);
75                 Point dot = new Point(12, 16);
76                 float angle = rand.Next(-randAngle, randAngle);//转动的度数  
77                 graph.TranslateTransform(dot.X, dot.Y);//移动光标到指定位置  
78                 graph.RotateTransform(angle);
79                 graph.DrawString(chars[i].ToString(), f, b, 1, 1, format);
80                 graph.RotateTransform(-angle);//转回去  
81                 graph.TranslateTransform(2, -dot.Y);//移动光标到指定位置  
82             }
83             //生成图片  
84             System.IO.MemoryStream ms = new System.IO.MemoryStream();
85             MemoryStream stream = new MemoryStream();
86             map.Save(stream, ImageFormat.Jpeg);
87             graph.Dispose();
88             map.Dispose();
89             return stream.ToArray();
90 
91 
92         }
93         #endregion  
94     }
95 }

1  <label class="panel-body">验证码：</label>
2  <input type="text" id="yzm" name="yzm" class="form-control" />&nbsp;&nbsp;</td>
3  <img id="ValidCode" style="cursor: pointer;" src="/SignIn/YanZhengMa" alt="验证码"  onclick="this.src=‘/SignIn/YanZhengMa?time=‘ + new Date().getTime();" />
4  <a href="#" id="Changes" data-toggle="modal" data-target="#mymodel">看不清,换一张</a>

 1  /// <summary>  
 2         /// 生成验证码  
 3         /// </summary>  
 4         /// <returns></returns>  
 5         public ActionResult YanZhengMa()
 6         {
 7             service_code sc = new service_code();
 8             string vVerificationCode = sc.RandCode();
 9             Session["vcode"] = vVerificationCode.ToLower();
10            // Safe.SessionAdd("vcode", vVerificationCode.ToLower(), 2);   //Session中保存验证码  
11             sc.CreateImage(vVerificationCode);
12             return File(sc.CreateImage(vVerificationCode), @"image/jpeg");
13         }