本文实例讲述了WinForm生成验证码图片的方法。分享给大家供大家参考，具体如下：
1、创建ValidCode类：
|
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
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
public class ValidCode{ #region Private Fields private const double PI = 3.1415926535897932384626433832795; private const double PI2 = 6.283185307179586476925286766559; //private readonly int _wordsLen = 4; private int _len; private CodeType _codetype; private readonly Single _jianju = (float)18.0; private readonly Single _height = (float)24.0; private string _checkCode; #endregion #region Public Property public string CheckCode { get { return _checkCode; } } #endregion #region Constructors /// <summary> /// public constructors /// </summary> /// <param name="len"> 验证码长度 </param> /// <param name="ctype"> 验证码类型：字母、数字、字母+ 数字 </param> public ValidCode(int len, CodeType ctype) { this._len = len; this._codetype = ctype; } #endregion #region Public Field public enum CodeType { Words, Numbers, Characters, Alphas } #endregion #region Private Methods private string GenerateNumbers() { string strOut = ""; System.Random random = new Random(); for (int i = 0; i < _len; i++) { string num = Convert.ToString(random.Next(10000) % 10); strOut += num; } return strOut.Trim(); } private string GenerateCharacters() { string strOut = ""; System.Random random = new Random(); for (int i = 0; i < _len; i++) { string num = Convert.ToString((char)(65 + random.Next(10000) % 26)); strOut += num; } return strOut.Trim(); } // private string GenerateAlphas() { string strOut = ""; string num = ""; System.Random random = new Random(); for (int i = 0; i < _len; i++) { if (random.Next(500) % 2 == 0) { num = Convert.ToString(random.Next(10000) % 10); } else { num = Convert.ToString((char)(65 + random.Next(10000) % 26)); } strOut += num; } return strOut.Trim(); } private System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase) { System.Drawing.Bitmap destBmp = new Bitmap(srcBmp.Width, srcBmp.Height); // 将位图背景填充为白色 System.Drawing.Graphics graph = System.Drawing.Graphics.FromImage(destBmp); graph.FillRectangle(new SolidBrush(System.Drawing.Color.White), 0, 0, destBmp.Width, destBmp.Height); graph.Dispose(); double dBaseAxisLen = bXDir ? (double)destBmp.Height : (double)destBmp.Width; for (int i = 0; i < destBmp.Width; i++) { for (int j = 0; j < destBmp.Height; j++) { double dx = 0; dx = bXDir ? (PI2 * (double)j) / dBaseAxisLen : (PI2 * (double)i) / dBaseAxisLen; dx += dPhase; double dy = Math.Sin(dx); // 取得当前点的颜色 int nOldX = 0, nOldY = 0; nOldX = bXDir ? i + (int)(dy * dMultValue) : i; nOldY = bXDir ? j : j + (int)(dy * dMultValue); System.Drawing.Color color = srcBmp.GetPixel(i, j); if (nOldX >= 0 && nOldX < destBmp.Width && nOldY >= 0 && nOldY < destBmp.Height) { destBmp.SetPixel(nOldX, nOldY, color); } } } return destBmp; } #endregion #region Public Methods public Stream CreateCheckCodeImage() { string checkCode; switch (_codetype) { case CodeType.Alphas: checkCode = GenerateAlphas(); break; case CodeType.Numbers: checkCode = GenerateNumbers(); break; case CodeType.Characters: checkCode = GenerateCharacters(); break; default: checkCode = GenerateAlphas(); break; } this._checkCode = checkCode; MemoryStream ms = null; // if (checkCode == null || checkCode.Trim() == String.Empty) return null; Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * _jianju)), (int)_height); Graphics g = Graphics.FromImage(image); try { Random random = new Random(); g.Clear(Color.White); // 画图片的背景噪音线 for (int i = 0; i < 18; i++) { int x1 = random.Next(image.Width); int x2 = random.Next(image.Width); int y1 = random.Next(image.Height); int y2 = random.Next(image.Height); g.DrawLine(new Pen(Color.FromArgb(random.Next()), 1), x1, y1, x2, y2); } Font font = new System.Drawing.Font("Times New Roman", 14, System.Drawing.FontStyle.Bold); LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true); if (_codetype != CodeType.Words) { for (int i = 0; i < checkCode.Length; i++) { g.DrawString(checkCode.Substring(i, 1), font, brush, 2 + i * _jianju, 1); } } else { g.DrawString(checkCode, font, brush, 2, 2); } // 画图片的前景噪音点 for (int i = 0; i < 150; i++) { int x = random.Next(image.Width); int y = random.Next(image.Height); image.SetPixel(x, y, Color.FromArgb(random.Next())); } // 画图片的波形滤镜效果 if (_codetype != CodeType.Words) { image = TwistImage(image, true, 3, 1); } // 画图片的边框线 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1); ms = new System.IO.MemoryStream(); image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif); } finally { g.Dispose(); image.Dispose(); } return ms; } #endregion} |
2、产生验证码图片代码：
|
1
2
3
|
//参数一：产生几个字符的验证码图片 参数二：验证码的形式(数字、字母、数字字母混合都有)ValidCode validCode = new ValidCode(5, ValidCode.CodeType.Alphas);this.pictureBox2.Image = Bitmap.FromStream(validCode.CreateCheckCodeImage()); |
希望本文所述对大家C#程序设计有所帮助。
