1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
| using System;
| using System.DrawingCore;
| using System.DrawingCore.Imaging;
| using System.IO;
|
| namespace DotNet.Utilities
| {
| public class VierificationCodeServices
| {
| /// <summary>
| /// 该方法用于生成指定位数的随机数
| /// </summary>
| /// <param name="VcodeNum">参数是随机数的位数</param>
| /// <returns>返回一个随机数字符串</returns>
| private static string RndNum(int VcodeNum)
| {
| //验证码可以显示的字符集合
| string Vchar = "0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f,g,h,i,j,k,l,m,n,p" +
| ",q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,I,J,K,L,M,N,P,P,Q" +
| ",R,S,T,U,V,W,X,Y,Z";
| string[] VcArray = Vchar.Split(new Char[] { ',' });//拆分成数组
| string code = "";//产生的随机数
| int temp = -1;//记录上次随机数值，尽量避避免生产几个一样的随机数
|
| Random rand = new Random();
| //采用一个简单的算法以保证生成随机数的不同
| for (int i = 1; i < VcodeNum + 1; i++)
| {
| if (temp != -1)
| {
| rand = new Random(i * temp * unchecked((int)DateTime.Now.Ticks));//初始化随机类
| }
| int t = rand.Next(61);//获取随机数
| if (temp != -1 && temp == t)
| {
| return RndNum(VcodeNum);//如果获取的随机数重复，则递归调用
| }
| temp = t;//把本次产生的随机数记录起来
| code += VcArray[t];//随机数的位数加一
| }
| return code;
| }
|
| /// <summary>
| /// 该方法是将生成的随机数写入图像文件
| /// </summary>
| /// <param name="code">code是一个随机数</param>
| /// <param name="numbers">生成位数（默认4位）</param>
| public static MemoryStream Create(out string code, int numbers = 4)
| {
| code = RndNum(numbers);
| Bitmap Img = null;
| Graphics g = null;
| MemoryStream ms = null;
| 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" };
|
| try
| {
| //定义图像的大小，生成图像的实例
| Img = new Bitmap((int)code.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 < code.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 Font(fonts[findex], 15, FontStyle.Bold);//字体
| Brush b = new 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(code.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
| }
| catch (Exception)
| {
|
| throw;
| }
| finally
| {
| g.Dispose();
| Img.Dispose();
| }
| return ms;
| }
| }
| }
|
|
