mvc实现图片验证码功能
这篇文章主要为大家详细介绍了mvc实现图片验证码,具有一定的参考价值,感兴趣的小伙伴们可以参考一下
mvc中实现图片验证码很简单,只需要创建一个 FileContentResult的方法,返回file就行
1 2 3 4 5 6 7 8 9 10 11 12 13 14 | /// <summary> /// 创建一个文件方法 /// </summary> /// <returns></returns> public FileContentResult GetCode() { //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) ValidateCode validCode = new ValidateCode(5, ValidateCode.CodeType.Alphas); //将图片转换为二进制 MemoryStream ms =validCode.CreateCheckCodeImage() as MemoryStream; dateCode = validCode.CheckCode; //通过 CheckCode获取当前的验证码 byte [] buffurPic = ms.ToArray(); return File(buffurPic, "image/jpeg" ); } |
以下是生成验证码代码:
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 | using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Drawing; using System.Drawing.Drawing2D; using System.IO; namespace Helper { public class ValidateCode { #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 /// /// public constructors /// /// 验证码长度 /// 验证码类型:字母、数字、字母+ 数字 public ValidateCode( 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 public 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(); } public 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(); } // public 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 } } |
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