1 public class ValidateCode
2 {
3 public ValidateCode()
4 {
5 }
6 /// <summary>
7 /// 验证码的最大长度
8 /// </summary>
9 public int MaxLength
10 {
11 get { return 10; }
12 }
13 /// <summary>
14 /// 验证码的最小长度
15 /// </summary>
16 public int MinLength
17 {
18 get { return 1; }
19 }
20 /// <summary>
21 /// 生成验证码
22 /// </summary>
23 /// <param name="length">指定验证码的长度</param>
24 /// <returns>验证码字符串</returns>
25 public string CreateValidateCode(int length)
26 {
27 int[] randMembers = new int[length];
28 int[] validateNums = new int[length];
29 string validateNumberStr = "";
30 //生成起始序列值
31 int seekSeek = unchecked((int)DateTime.Now.Ticks);
32 Random seekRand = new Random(seekSeek);
33 int beginSeek = (int)seekRand.Next(0, Int32.MaxValue - length * 10000);
34 int[] seeks = new int[length];
35 for (int i = 0; i < length; i++)
36 {
37 beginSeek += 10000;
38 seeks[i] = beginSeek;
39 }
40 //生成随机数字
41 for (int i = 0; i < length; i++)
42 {
43 Random rand = new Random(seeks[i]);
44 int pownum = 1 * (int)Math.Pow(10, length);
45 randMembers[i] = rand.Next(pownum, Int32.MaxValue);
46 }
47 //抽取随机数字
48 for (int i = 0; i < length; i++)
49 {
50 string numStr = randMembers[i].ToString();
51 int numLength = numStr.Length;
52 Random rand = new Random();
53 int numPosition = rand.Next(0, numLength - 1);
54 validateNums[i] = Int32.Parse(numStr.Substring(numPosition, 1));
55 }
56 //生成验证码
57 for (int i = 0; i < length; i++)
58 {
59 validateNumberStr += validateNums[i].ToString();
60 }
61 return validateNumberStr;
62 }
63 //======================在webform中的写法============================
64 /// <summary>
65 /// 创建验证码的图片
66 /// </summary>
67 /// <param name="containsPage">要输出到的page对象</param>
68 /// <param name="validateNum">验证码</param>
69 public void CreateValidateGraphic(string validateCode, HttpContext context)
70 {
71 Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length * 12.0), 22);
72 Graphics g = Graphics.FromImage(image);
73 try
74 {
75 //生成随机生成器
76 Random random = new Random();
77 //清空图片背景色
78 g.Clear(Color.White);
79 //画图片的干扰线
80 for (int i = 0; i < 25; i++)
81 {
82 int x1 = random.Next(image.Width);
83 int x2 = random.Next(image.Width);
84 int y1 = random.Next(image.Height);
85 int y2 = random.Next(image.Height);
86 g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
87 }
88 Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));
89 LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),
90 Color.Blue, Color.DarkRed, 1.2f, true);
91 g.DrawString(validateCode, font, brush, 3, 2);
92 //画图片的前景干扰点
93 for (int i = 0; i < 100; i++)
94 {
95 int x = random.Next(image.Width);
96 int y = random.Next(image.Height);
97 image.SetPixel(x, y, Color.FromArgb(random.Next()));
98 }
99 //画图片的边框线
100 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
101 //保存图片数据
102 MemoryStream stream = new MemoryStream();
103 image.Save(stream, ImageFormat.Jpeg);
104 //输出图片流
105 context.Response.Clear();
106 context.Response.ContentType = "image/jpeg";
107 context.Response.BinaryWrite(stream.ToArray());
108 }
109 finally
110 {
111 g.Dispose();
112 image.Dispose();
113 }
114 }
115 /// <summary>
116 /// 得到验证码图片的长度
117 /// </summary>
118 /// <param name="validateNumLength">验证码的长度</param>
119 /// <returns></returns>
120 public static int GetImageWidth(int validateNumLength)
121 {
122 return (int)(validateNumLength * 12.0);
123 }
124 /// <summary>
125 /// 得到验证码的高度
126 /// </summary>
127 /// <returns></returns>
128 public static double GetImageHeight()
129 {
130 return 22.5;
131 }
132
133 //===============在mvc中的写法=========================
134 //C# MVC 升级版
135 /// <summary>
136 /// 创建验证码的图片
137 /// </summary>
138 /// <param name="containsPage">要输出到的page对象</param>
139 /// <param name="validateNum">验证码</param>
140 public byte[] CreateValidateGraphic(string validateCode)
141 {
142 Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length * 12.0), 22);
143 Graphics g = Graphics.FromImage(image);
144 try
145 {
146 //生成随机生成器
147 Random random = new Random();
148 //清空图片背景色
149 g.Clear(Color.White);
150 //画图片的干扰线
151 for (int i = 0; i < 25; i++)
152 {
153 int x1 = random.Next(image.Width);
154 int x2 = random.Next(image.Width);
155 int y1 = random.Next(image.Height);
156 int y2 = random.Next(image.Height);
157 g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
158 }
159 Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));
160 LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),
161 Color.Blue, Color.DarkRed, 1.2f, true);
162 g.DrawString(validateCode, font, brush, 3, 2);
163 //画图片的前景干扰点
164 for (int i = 0; i < 100; i++)
165 {
166 int x = random.Next(image.Width);
167 int y = random.Next(image.Height);
168 image.SetPixel(x, y, Color.FromArgb(random.Next()));
169 }
170 //画图片的边框线
171 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
172 //保存图片数据
173 MemoryStream stream = new MemoryStream();
174 image.Save(stream, ImageFormat.Jpeg);
175 //输出图片流
176 return stream.ToArray();
177 }
178 finally
179 {
180 g.Dispose();
181 image.Dispose();
182 }
183 }
184 }
上面是生成验证码以及验证码图片
下面是怎么使用：
1 string code=vCode.CreateValidateCode(4);//得到生成的验证码
2 byte[] bcode=vCode.CreateValidateGraphic(code);//将验证码创建成图片的二进制格式