验证码帮助类
1 using System; 2 using System.Web; 3 using System.Drawing; 4 using System.Security.Cryptography; 5 6 namespace DotNet.Utilities 7 { 8 /// <summary> 9 /// 验证码类 10 /// </summary> 11 public class Rand 12 { 13 #region 生成随机数字 14 /// <summary> 15 /// 生成随机数字 16 /// </summary> 17 /// <param name="length">生成长度</param> 18 public static string Number(int Length) 19 { 20 return Number(Length, false); 21 } 22 23 /// <summary> 24 /// 生成随机数字 25 /// </summary> 26 /// <param name="Length">生成长度</param> 27 /// <param name="Sleep">是否要在生成前将当前线程阻止以避免重复</param> 28 public static string Number(int Length, bool Sleep) 29 { 30 if (Sleep) System.Threading.Thread.Sleep(3); 31 string result = ""; 32 System.Random random = new Random(); 33 for (int i = 0; i < Length; i++) 34 { 35 result += random.Next(10).ToString(); 36 } 37 return result; 38 } 39 #endregion 40 41 #region 生成随机字母与数字 42 /// <summary> 43 /// 生成随机字母与数字 44 /// </summary> 45 /// <param name="IntStr">生成长度</param> 46 public static string Str(int Length) 47 { 48 return Str(Length, false); 49 } 50 51 /// <summary> 52 /// 生成随机字母与数字 53 /// </summary> 54 /// <param name="Length">生成长度</param> 55 /// <param name="Sleep">是否要在生成前将当前线程阻止以避免重复</param> 56 public static string Str(int Length, bool Sleep) 57 { 58 if (Sleep) System.Threading.Thread.Sleep(3); 59 char[] Pattern = new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' }; 60 string result = ""; 61 int n = Pattern.Length; 62 System.Random random = new Random(~unchecked((int)DateTime.Now.Ticks)); 63 for (int i = 0; i < Length; i++) 64 { 65 int rnd = random.Next(0, n); 66 result += Pattern[rnd]; 67 } 68 return result; 69 } 70 #endregion 71 72 #region 生成随机纯字母随机数 73 /// <summary> 74 /// 生成随机纯字母随机数 75 /// </summary> 76 /// <param name="IntStr">生成长度</param> 77 public static string Str_char(int Length) 78 { 79 return Str_char(Length, false); 80 } 81 82 /// <summary> 83 /// 生成随机纯字母随机数 84 /// </summary> 85 /// <param name="Length">生成长度</param> 86 /// <param name="Sleep">是否要在生成前将当前线程阻止以避免重复</param> 87 public static string Str_char(int Length, bool Sleep) 88 { 89 if (Sleep) System.Threading.Thread.Sleep(3); 90 char[] Pattern = new char[] { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' }; 91 string result = ""; 92 int n = Pattern.Length; 93 System.Random random = new Random(~unchecked((int)DateTime.Now.Ticks)); 94 for (int i = 0; i < Length; i++) 95 { 96 int rnd = random.Next(0, n); 97 result += Pattern[rnd]; 98 } 99 return result; 100 } 101 #endregion 102 } 103 104 /// <summary> 105 /// 验证图片类 106 /// </summary> 107 public class YZMHelper 108 { 109 #region 私有字段 110 private string text; 111 private Bitmap image; 112 private int letterCount = 4; //验证码位数 113 private int letterWidth = 16; //单个字体的宽度范围 114 private int letterHeight = 20; //单个字体的高度范围 115 private static byte[] randb = new byte[4]; 116 private static RNGCryptoServiceProvider rand = new RNGCryptoServiceProvider(); 117 private Font[] fonts = 118 { 119 new Font(new FontFamily("Times New Roman"),10 +Next(1),System.Drawing.FontStyle.Regular), 120 new Font(new FontFamily("Georgia"), 10 + Next(1),System.Drawing.FontStyle.Regular), 121 new Font(new FontFamily("Arial"), 10 + Next(1),System.Drawing.FontStyle.Regular), 122 new Font(new FontFamily("Comic Sans MS"), 10 + Next(1),System.Drawing.FontStyle.Regular) 123 }; 124 #endregion 125 126 #region 公有属性 127 /// <summary> 128 /// 验证码 129 /// </summary> 130 public string Text 131 { 132 get { return this.text; } 133 } 134 135 /// <summary> 136 /// 验证码图片 137 /// </summary> 138 public Bitmap Image 139 { 140 get { return this.image; } 141 } 142 #endregion 143 144 #region 构造函数 145 public YZMHelper() 146 { 147 HttpContext.Current.Response.Expires = 0; 148 HttpContext.Current.Response.Buffer = true; 149 HttpContext.Current.Response.ExpiresAbsolute = DateTime.Now.AddSeconds(-1); 150 HttpContext.Current.Response.AddHeader("pragma", "no-cache"); 151 HttpContext.Current.Response.CacheControl = "no-cache"; 152 this.text = Rand.Number(4); 153 CreateImage(); 154 } 155 #endregion 156 157 #region 私有方法 158 /// <summary> 159 /// 获得下一个随机数 160 /// </summary> 161 /// <param name="max">最大值</param> 162 private static int Next(int max) 163 { 164 rand.GetBytes(randb); 165 int value = BitConverter.ToInt32(randb, 0); 166 value = value % (max + 1); 167 if (value < 0) value = -value; 168 return value; 169 } 170 171 /// <summary> 172 /// 获得下一个随机数 173 /// </summary> 174 /// <param name="min">最小值</param> 175 /// <param name="max">最大值</param> 176 private static int Next(int min, int max) 177 { 178 int value = Next(max - min) + min; 179 return value; 180 } 181 #endregion 182 183 #region 公共方法 184 /// <summary> 185 /// 绘制验证码 186 /// </summary> 187 public void CreateImage() 188 { 189 int int_ImageWidth = this.text.Length * letterWidth; 190 Bitmap image = new Bitmap(int_ImageWidth, letterHeight); 191 Graphics g = Graphics.FromImage(image); 192 g.Clear(Color.White); 193 for (int i = 0; i < 2; i++) 194 { 195 int x1 = Next(image.Width - 1); 196 int x2 = Next(image.Width - 1); 197 int y1 = Next(image.Height - 1); 198 int y2 = Next(image.Height - 1); 199 g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2); 200 } 201 int _x = -12, _y = 0; 202 for (int int_index = 0; int_index < this.text.Length; int_index++) 203 { 204 _x += Next(12, 16); 205 _y = Next(-2, 2); 206 string str_char = this.text.Substring(int_index, 1); 207 str_char = Next(1) == 1 ? str_char.ToLower() : str_char.ToUpper(); 208 Brush newBrush = new SolidBrush(GetRandomColor()); 209 Point thePos = new Point(_x, _y); 210 g.DrawString(str_char, fonts[Next(fonts.Length - 1)], newBrush, thePos); 211 } 212 for (int i = 0; i < 10; i++) 213 { 214 int x = Next(image.Width - 1); 215 int y = Next(image.Height - 1); 216 image.SetPixel(x, y, Color.FromArgb(Next(0, 255), Next(0, 255), Next(0, 255))); 217 } 218 image = TwistImage(image, true, Next(1, 3), Next(4, 6)); 219 g.DrawRectangle(new Pen(Color.LightGray, 1), 0, 0, int_ImageWidth - 1, (letterHeight - 1)); 220 this.image = image; 221 } 222 223 /// <summary> 224 /// 字体随机颜色 225 /// </summary> 226 public Color GetRandomColor() 227 { 228 Random RandomNum_First = new Random((int)DateTime.Now.Ticks); 229 System.Threading.Thread.Sleep(RandomNum_First.Next(50)); 230 Random RandomNum_Sencond = new Random((int)DateTime.Now.Ticks); 231 int int_Red = RandomNum_First.Next(180); 232 int int_Green = RandomNum_Sencond.Next(180); 233 int int_Blue = (int_Red + int_Green > 300) ? 0 : 400 - int_Red - int_Green; 234 int_Blue = (int_Blue > 255) ? 255 : int_Blue; 235 return Color.FromArgb(int_Red, int_Green, int_Blue); 236 } 237 238 /// <summary> 239 /// 正弦曲线Wave扭曲图片 240 /// </summary> 241 /// <param name="srcBmp">图片路径</param> 242 /// <param name="bXDir">如果扭曲则选择为True</param> 243 /// <param name="nMultValue">波形的幅度倍数,越大扭曲的程度越高,一般为3</param> 244 /// <param name="dPhase">波形的起始相位,取值区间[0-2*PI)</param> 245 public System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase) 246 { 247 double PI = 6.283185307179586476925286766559; 248 Bitmap destBmp = new Bitmap(srcBmp.Width, srcBmp.Height); 249 Graphics graph = Graphics.FromImage(destBmp); 250 graph.FillRectangle(new SolidBrush(Color.White), 0, 0, destBmp.Width, destBmp.Height); 251 graph.Dispose(); 252 double dBaseAxisLen = bXDir ? (double)destBmp.Height : (double)destBmp.Width; 253 for (int i = 0; i < destBmp.Width; i++) 254 { 255 for (int j = 0; j < destBmp.Height; j++) 256 { 257 double dx = 0; 258 dx = bXDir ? (PI * (double)j) / dBaseAxisLen : (PI * (double)i) / dBaseAxisLen; 259 dx += dPhase; 260 double dy = Math.Sin(dx); 261 int nOldX = 0, nOldY = 0; 262 nOldX = bXDir ? i + (int)(dy * dMultValue) : i; 263 nOldY = bXDir ? j : j + (int)(dy * dMultValue); 264 265 Color color = srcBmp.GetPixel(i, j); 266 if (nOldX >= 0 && nOldX < destBmp.Width 267 && nOldY >= 0 && nOldY < destBmp.Height) 268 { 269 destBmp.SetPixel(nOldX, nOldY, color); 270 } 271 } 272 } 273 srcBmp.Dispose(); 274 return destBmp; 275 } 276 #endregion 277 } 278 }