mcs/class/System.Web/System.Web/HttpUtility.cs

   1 //
   2 // System.Web.HttpUtility
   3 //
   4 // Authors:
   5 //   Patrik Torstensson (Patrik.Torstensson@labs2.com)
   6 //   Wictor Wilén (decode/encode functions) (wictor@ibizkit.se)
   7 //   Tim Coleman (tim@timcoleman.com)
   8 //   Gonzalo Paniagua Javier (gonzalo@ximian.com)
   9 //
  10 // Copyright (C) 2005-2010 Novell, Inc (http://www.novell.com)
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System.Collections;
  33 using System.Collections.Generic;
  34 using System.Collections.Specialized;
  35 using System.Globalization;
  36 using System.IO;
  37 using System.Security.Permissions;
  38 using System.Text;
  39 using System.Web.Util;
  40
  41 namespace System.Web {
  42
  43 #if !MOBILE
  44         // CAS - no InheritanceDemand here as the class is sealed
  45         [AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
  46 #endif
  47         public sealed class HttpUtility
  48         {
  49                 sealed class HttpQSCollection : NameValueCollection
  50                 {
  51                         public override string ToString ()
  52                         {
  53                                 int count = Count;
  54                                 if (count == 0)
  55                                         return "";
  56                                 StringBuilder sb = new StringBuilder ();
  57                                 string [] keys = AllKeys;
  58                                 for (int i = 0; i < count; i++) {
  59                                         sb.AppendFormat ("{0}={1}&", keys [i], UrlEncode (this [keys [i]]));
  60                                 }
  61                                 if (sb.Length > 0)
  62                                         sb.Length--;
  63                                 return sb.ToString ();
  64                         }
  65                 }
  66
  67                 #region Constructors
  68
  69                 public HttpUtility ()
  70                 {
  71                 }
  72
  73                 #endregion // Constructors
  74
  75                 #region Methods
  76
  77                 public static void HtmlAttributeEncode (string s, TextWriter output)
  78                 {
  79                         if (output == null) {
  80                                 throw new ArgumentNullException ("output");
  81                         }
  82                         HttpEncoder.Current.HtmlAttributeEncode (s, output);
  83                 }
  84
  85                 public static string HtmlAttributeEncode (string s)
  86                 {
  87                         if (s == null)
  88                                 return null;
  89
  90                         using (var sw = new StringWriter ()) {
  91                                 HttpEncoder.Current.HtmlAttributeEncode (s, sw);
  92                                 return sw.ToString ();
  93                         }
  94                 }
  95
  96                 public static string UrlDecode (string str)
  97                 {
  98                         return UrlDecode(str, Encoding.UTF8);
  99                 }
 100
 101                 static char [] GetChars (MemoryStream b, Encoding e)
 102                 {
 103                         return e.GetChars (b.GetBuffer (), 0, (int) b.Length);
 104                 }
 105
 106                 static void WriteCharBytes (IList buf, char ch, Encoding e)
 107                 {
 108                         if (ch > 255) {
 109                                 foreach (byte b in e.GetBytes (new char[] { ch }))
 110                                         buf.Add (b);
 111                         } else
 112                                 buf.Add ((byte)ch);
 113                 }
 114
 115                 public static string UrlDecode (string s, Encoding e)
 116                 {
 117                         if (null == s)
 118                                 return null;
 119
 120                         if (s.IndexOf ('%') == -1 && s.IndexOf ('+') == -1)
 121                                 return s;
 122
 123                         if (e == null)
 124                                 e = Encoding.UTF8;
 125
 126                         long len = s.Length;
 127                         var bytes = new List <byte> ();
 128                         int xchar;
 129                         char ch;
 130
 131                         for (int i = 0; i < len; i++) {
 132                                 ch = s [i];
 133                                 if (ch == '%' && i + 2 < len && s [i + 1] != '%') {
 134                                         if (s [i + 1] == 'u' && i + 5 < len) {
 135                                                 // unicode hex sequence
 136                                                 xchar = GetChar (s, i + 2, 4);
 137                                                 if (xchar != -1) {
 138                                                         WriteCharBytes (bytes, (char)xchar, e);
 139                                                         i += 5;
 140                                                 } else
 141                                                         WriteCharBytes (bytes, '%', e);
 142                                         } else if ((xchar = GetChar (s, i + 1, 2)) != -1) {
 143                                                 WriteCharBytes (bytes, (char)xchar, e);
 144                                                 i += 2;
 145                                         } else {
 146                                                 WriteCharBytes (bytes, '%', e);
 147                                         }
 148                                         continue;
 149                                 }
 150
 151                                 if (ch == '+')
 152                                         WriteCharBytes (bytes, ' ', e);
 153                                 else
 154                                         WriteCharBytes (bytes, ch, e);
 155                         }
 156
 157                         byte[] buf = bytes.ToArray ();
 158                         bytes = null;
 159                         return e.GetString (buf);
 160
 161                 }
 162
 163                 public static string UrlDecode (byte [] bytes, Encoding e)
 164                 {
 165                         if (bytes == null)
 166                                 return null;
 167
 168                         return UrlDecode (bytes, 0, bytes.Length, e);
 169                 }
 170
 171                 static int GetInt (byte b)
 172                 {
 173                         char c = (char) b;
 174                         if (c >= '0' && c <= '9')
 175                                 return c - '0';
 176
 177                         if (c >= 'a' && c <= 'f')
 178                                 return c - 'a' + 10;
 179
 180                         if (c >= 'A' && c <= 'F')
 181                                 return c - 'A' + 10;
 182
 183                         return -1;
 184                 }
 185
 186                 static int GetChar (byte [] bytes, int offset, int length)
 187                 {
 188                         int value = 0;
 189                         int end = length + offset;
 190                         for (int i = offset; i < end; i++) {
 191                                 int current = GetInt (bytes [i]);
 192                                 if (current == -1)
 193                                         return -1;
 194                                 value = (value << 4) + current;
 195                         }
 196
 197                         return value;
 198                 }
 199
 200                 static int GetChar (string str, int offset, int length)
 201                 {
 202                         int val = 0;
 203                         int end = length + offset;
 204                         for (int i = offset; i < end; i++) {
 205                                 char c = str [i];
 206                                 if (c > 127)
 207                                         return -1;
 208
 209                                 int current = GetInt ((byte) c);
 210                                 if (current == -1)
 211                                         return -1;
 212                                 val = (val << 4) + current;
 213                         }
 214
 215                         return val;
 216                 }
 217
 218                 public static string UrlDecode (byte [] bytes, int offset, int count, Encoding e)
 219                 {
 220                         if (bytes == null)
 221                                 return null;
 222                         if (count == 0)
 223                                 return String.Empty;
 224
 225                         if (bytes == null)
 226                                 throw new ArgumentNullException ("bytes");
 227
 228                         if (offset < 0 || offset > bytes.Length)
 229                                 throw new ArgumentOutOfRangeException ("offset");
 230
 231                         if (count < 0 || offset + count > bytes.Length)
 232                                 throw new ArgumentOutOfRangeException ("count");
 233
 234                         StringBuilder output = new StringBuilder ();
 235                         MemoryStream acc = new MemoryStream ();
 236
 237                         int end = count + offset;
 238                         int xchar;
 239                         for (int i = offset; i < end; i++) {
 240                                 if (bytes [i] == '%' && i + 2 < count && bytes [i + 1] != '%') {
 241                                         if (bytes [i + 1] == (byte) 'u' && i + 5 < end) {
 242                                                 if (acc.Length > 0) {
 243                                                         output.Append (GetChars (acc, e));
 244                                                         acc.SetLength (0);
 245                                                 }
 246                                                 xchar = GetChar (bytes, i + 2, 4);
 247                                                 if (xchar != -1) {
 248                                                         output.Append ((char) xchar);
 249                                                         i += 5;
 250                                                         continue;
 251                                                 }
 252                                         } else if ((xchar = GetChar (bytes, i + 1, 2)) != -1) {
 253                                                 acc.WriteByte ((byte) xchar);
 254                                                 i += 2;
 255                                                 continue;
 256                                         }
 257                                 }
 258
 259                                 if (acc.Length > 0) {
 260                                         output.Append (GetChars (acc, e));
 261                                         acc.SetLength (0);
 262                                 }
 263
 264                                 if (bytes [i] == '+') {
 265                                         output.Append (' ');
 266                                 } else {
 267                                         output.Append ((char) bytes [i]);
 268                                 }
 269                         }
 270
 271                         if (acc.Length > 0) {
 272                                 output.Append (GetChars (acc, e));
 273                         }
 274
 275                         acc = null;
 276                         return output.ToString ();
 277                 }
 278
 279                 public static byte [] UrlDecodeToBytes (byte [] bytes)
 280                 {
 281                         if (bytes == null)
 282                                 return null;
 283
 284                         return UrlDecodeToBytes (bytes, 0, bytes.Length);
 285                 }
 286
 287                 public static byte [] UrlDecodeToBytes (string str)
 288                 {
 289                         return UrlDecodeToBytes (str, Encoding.UTF8);
 290                 }
 291
 292                 public static byte [] UrlDecodeToBytes (string str, Encoding e)
 293                 {
 294                         if (str == null)
 295                                 return null;
 296
 297                         if (e == null)
 298                                 throw new ArgumentNullException ("e");
 299
 300                         return UrlDecodeToBytes (e.GetBytes (str));
 301                 }
 302
 303                 public static byte [] UrlDecodeToBytes (byte [] bytes, int offset, int count)
 304                 {
 305                         if (bytes == null)
 306                                 return null;
 307                         if (count == 0)
 308                                 return new byte [0];
 309
 310                         int len = bytes.Length;
 311                         if (offset < 0 || offset >= len)
 312                                 throw new ArgumentOutOfRangeException("offset");
 313
 314                         if (count < 0 || offset > len - count)
 315                                 throw new ArgumentOutOfRangeException("count");
 316
 317                         MemoryStream result = new MemoryStream ();
 318                         int end = offset + count;
 319                         for (int i = offset; i < end; i++){
 320                                 char c = (char) bytes [i];
 321                                 if (c == '+') {
 322                                         c = ' ';
 323                                 } else if (c == '%' && i < end - 2) {
 324                                         int xchar = GetChar (bytes, i + 1, 2);
 325                                         if (xchar != -1) {
 326                                                 c = (char) xchar;
 327                                                 i += 2;
 328                                         }
 329                                 }
 330                                 result.WriteByte ((byte) c);
 331                         }
 332
 333                         return result.ToArray ();
 334                 }
 335
 336                 public static string UrlEncode(string str)
 337                 {
 338                         return UrlEncode(str, Encoding.UTF8);
 339                 }
 340
 341                 public static string UrlEncode (string s, Encoding Enc)
 342                 {
 343                         if (s == null)
 344                                 return null;
 345
 346                         if (s == String.Empty)
 347                                 return String.Empty;
 348
 349                         bool needEncode = false;
 350                         int len = s.Length;
 351                         for (int i = 0; i < len; i++) {
 352                                 char c = s [i];
 353                                 if ((c < '0') || (c < 'A' && c > '9') || (c > 'Z' && c < 'a') || (c > 'z')) {
 354                                         if (HttpEncoder.NotEncoded (c))
 355                                                 continue;
 356
 357                                         needEncode = true;
 358                                         break;
 359                                 }
 360                         }
 361
 362                         if (!needEncode)
 363                                 return s;
 364
 365                         // avoided GetByteCount call
 366                         byte [] bytes = new byte[Enc.GetMaxByteCount(s.Length)];
 367                         int realLen = Enc.GetBytes (s, 0, s.Length, bytes, 0);
 368                         return Encoding.ASCII.GetString (UrlEncodeToBytes (bytes, 0, realLen));
 369                 }
 370
 371                 public static string UrlEncode (byte [] bytes)
 372                 {
 373                         if (bytes == null)
 374                                 return null;
 375
 376                         if (bytes.Length == 0)
 377                                 return String.Empty;
 378
 379                         return Encoding.ASCII.GetString (UrlEncodeToBytes (bytes, 0, bytes.Length));
 380                 }
 381
 382                 public static string UrlEncode (byte [] bytes, int offset, int count)
 383                 {
 384                         if (bytes == null)
 385                                 return null;
 386
 387                         if (bytes.Length == 0)
 388                                 return String.Empty;
 389
 390                         return Encoding.ASCII.GetString (UrlEncodeToBytes (bytes, offset, count));
 391                 }
 392
 393                 public static byte [] UrlEncodeToBytes (string str)
 394                 {
 395                         return UrlEncodeToBytes (str, Encoding.UTF8);
 396                 }
 397
 398                 public static byte [] UrlEncodeToBytes (string str, Encoding e)
 399                 {
 400                         if (str == null)
 401                                 return null;
 402
 403                         if (str.Length == 0)
 404                                 return new byte [0];
 405
 406                         byte [] bytes = e.GetBytes (str);
 407                         return UrlEncodeToBytes (bytes, 0, bytes.Length);
 408                 }
 409
 410                 public static byte [] UrlEncodeToBytes (byte [] bytes)
 411                 {
 412                         if (bytes == null)
 413                                 return null;
 414
 415                         if (bytes.Length == 0)
 416                                 return new byte [0];
 417
 418                         return UrlEncodeToBytes (bytes, 0, bytes.Length);
 419                 }
 420
 421                 public static byte [] UrlEncodeToBytes (byte [] bytes, int offset, int count)
 422                 {
 423                         if (bytes == null)
 424                                 return null;
 425                         return HttpEncoder.Current.UrlEncode (bytes, offset, count);
 426                 }
 427
 428                 public static string UrlEncodeUnicode (string str)
 429                 {
 430                         if (str == null)
 431                                 return null;
 432
 433                         return Encoding.ASCII.GetString (UrlEncodeUnicodeToBytes (str));
 434                 }
 435
 436                 public static byte [] UrlEncodeUnicodeToBytes (string str)
 437                 {
 438                         if (str == null)
 439                                 return null;
 440
 441                         if (str.Length == 0)
 442                                 return new byte [0];
 443
 444                         MemoryStream result = new MemoryStream (str.Length);
 445                         foreach (char c in str){
 446                                 HttpEncoder.UrlEncodeChar (c, result, true);
 447                         }
 448                         return result.ToArray ();
 449                 }
 450
 451                 /// <summary>
 452                 /// Decodes an HTML-encoded string and returns the decoded string.
 453                 /// </summary>
 454                 /// <param name="s">The HTML string to decode. </param>
 455                 /// <returns>The decoded text.</returns>
 456                 public static string HtmlDecode (string s)
 457                 {
 458                         if (s == null)
 459                                 return null;
 460
 461                         using (var sw = new StringWriter ()) {
 462                                 HttpEncoder.Current.HtmlDecode (s, sw);
 463                                 return sw.ToString ();
 464                         }
 465                 }
 466
 467                 /// <summary>
 468                 /// Decodes an HTML-encoded string and sends the resulting output to a TextWriter output stream.
 469                 /// </summary>
 470                 /// <param name="s">The HTML string to decode</param>
 471                 /// <param name="output">The TextWriter output stream containing the decoded string. </param>
 472                 public static void HtmlDecode(string s, TextWriter output)
 473                 {
 474                         if (output == null) {
 475                                 throw new ArgumentNullException ("output");
 476                         }
 477
 478                         if (!String.IsNullOrEmpty (s)) {
 479                                 HttpEncoder.Current.HtmlDecode (s, output);
 480                         }
 481                 }
 482
 483                 public static string HtmlEncode (string s)
 484                 {
 485                         if (s == null)
 486                                 return null;
 487
 488                         using (var sw = new StringWriter ()) {
 489                                 HttpEncoder.Current.HtmlEncode (s, sw);
 490                                 return sw.ToString ();
 491                         }
 492                 }
 493
 494                 /// <summary>
 495                 /// HTML-encodes a string and sends the resulting output to a TextWriter output stream.
 496                 /// </summary>
 497                 /// <param name="s">The string to encode. </param>
 498                 /// <param name="output">The TextWriter output stream containing the encoded string. </param>
 499                 public static void HtmlEncode(string s, TextWriter output)
 500                 {
 501                         if (output == null) {
 502                                 throw new ArgumentNullException ("output");
 503                         }
 504
 505                         if (!String.IsNullOrEmpty (s)) {
 506                                 HttpEncoder.Current.HtmlEncode (s, output);
 507                         }
 508                 }
 509                 public static string HtmlEncode (object value)
 510                 {
 511                         if (value == null)
 512                                 return null;
 513
 514 #if !(MOBILE || NO_SYSTEM_WEB_DEPENDENCY)
 515                         IHtmlString htmlString = value as IHtmlString;
 516                         if (htmlString != null)
 517                                 return htmlString.ToHtmlString ();
 518 #endif
 519
 520                         return HtmlEncode (value.ToString ());
 521                 }
 522
 523                 public static string JavaScriptStringEncode (string value)
 524                 {
 525                         return JavaScriptStringEncode (value, false);
 526                 }
 527
 528                 public static string JavaScriptStringEncode (string value, bool addDoubleQuotes)
 529                 {
 530                         if (String.IsNullOrEmpty (value))
 531                                 return addDoubleQuotes ? "\"\"" : String.Empty;
 532
 533                         int len = value.Length;
 534                         bool needEncode = false;
 535                         char c;
 536                         for (int i = 0; i < len; i++) {
 537                                 c = value [i];
 538
 539                                 if (c >= 0 && c <= 31 || c == 34 || c == 39 || c == 60 || c == 62 || c == 92) {
 540                                         needEncode = true;
 541                                         break;
 542                                 }
 543                         }
 544
 545                         if (!needEncode)
 546                                 return addDoubleQuotes ? "\"" + value + "\"" : value;
 547
 548                         var sb = new StringBuilder ();
 549                         if (addDoubleQuotes)
 550                                 sb.Append ('"');
 551
 552                         for (int i = 0; i < len; i++) {
 553                                 c = value [i];
 554                                 if (c >= 0 && c <= 7 || c == 11 || c >= 14 && c <= 31 || c == 39 || c == 60 || c == 62)
 555                                         sb.AppendFormat ("\\u{0:x4}", (int)c);
 556                                 else switch ((int)c) {
 557                                                 case 8:
 558                                                         sb.Append ("\\b");
 559                                                         break;
 560
 561                                                 case 9:
 562                                                         sb.Append ("\\t");
 563                                                         break;
 564
 565                                                 case 10:
 566                                                         sb.Append ("\\n");
 567                                                         break;
 568
 569                                                 case 12:
 570                                                         sb.Append ("\\f");
 571                                                         break;
 572
 573                                                 case 13:
 574                                                         sb.Append ("\\r");
 575                                                         break;
 576
 577                                                 case 34:
 578                                                         sb.Append ("\\\"");
 579                                                         break;
 580
 581                                                 case 92:
 582                                                         sb.Append ("\\\\");
 583                                                         break;
 584
 585                                                 default:
 586                                                         sb.Append (c);
 587                                                         break;
 588                                         }
 589                         }
 590
 591                         if (addDoubleQuotes)
 592                                 sb.Append ('"');
 593
 594                         return sb.ToString ();
 595                 }
 596                 public static string UrlPathEncode (string s)
 597                 {
 598                         return HttpEncoder.Current.UrlPathEncode (s);
 599                 }
 600
 601                 public static NameValueCollection ParseQueryString (string query)
 602                 {
 603                         return ParseQueryString (query, Encoding.UTF8);
 604                 }
 605
 606                 public static NameValueCollection ParseQueryString (string query, Encoding encoding)
 607                 {
 608                         if (query == null)
 609                                 throw new ArgumentNullException ("query");
 610                         if (encoding == null)
 611                                 throw new ArgumentNullException ("encoding");
 612                         if (query.Length == 0 || (query.Length == 1 && query[0] == '?'))
 613                                 return new HttpQSCollection ();
 614                         if (query[0] == '?')
 615                                 query = query.Substring (1);
 616
 617                         NameValueCollection result = new HttpQSCollection ();
 618                         ParseQueryString (query, encoding, result);
 619                         return result;
 620                 }
 621
 622                 internal static void ParseQueryString (string query, Encoding encoding, NameValueCollection result)
 623                 {
 624                         if (query.Length == 0)
 625                                 return;
 626
 627                         string decoded = HtmlDecode (query);
 628                         int decodedLength = decoded.Length;
 629                         int namePos = 0;
 630                         bool first = true;
 631                         while (namePos <= decodedLength) {
 632                                 int valuePos = -1, valueEnd = -1;
 633                                 for (int q = namePos; q < decodedLength; q++) {
 634                                         if (valuePos == -1 && decoded [q] == '=') {
 635                                                 valuePos = q + 1;
 636                                         } else if (decoded [q] == '&') {
 637                                                 valueEnd = q;
 638                                                 break;
 639                                         }
 640                                 }
 641
 642                                 if (first) {
 643                                         first = false;
 644                                         if (decoded [namePos] == '?')
 645                                                 namePos++;
 646                                 }
 647
 648                                 string name, value;
 649                                 if (valuePos == -1) {
 650                                         name = null;
 651                                         valuePos = namePos;
 652                                 } else {
 653                                         name = UrlDecode (decoded.Substring (namePos, valuePos - namePos - 1), encoding);
 654                                 }
 655                                 if (valueEnd < 0) {
 656                                         namePos = -1;
 657                                         valueEnd = decoded.Length;
 658                                 } else {
 659                                         namePos = valueEnd + 1;
 660                                 }
 661                                 value = UrlDecode (decoded.Substring (valuePos, valueEnd - valuePos), encoding);
 662
 663                                 result.Add (name, value);
 664                                 if (namePos == -1)
 665                                         break;
 666                         }
 667                 }
 668                 #endregion // Methods
 669         }
 670 }
 671