mcs/class/corlib/System/String.cs

   1 // -*- Mode: C++; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
   2 //
   3 // System.String.cs
   4 //
   5 // Author:
   6 //   Jeffrey Stedfast (fejj@ximian.com)
   7 //
   8 // (C) 2001 Ximian, Inc.  http://www.ximian.com
   9 //
  10
  11 // FIXME: from what I gather from msdn, when a function is to return an empty string
  12 //        we should be returning this.Empty - some methods do this and others don't.
  13
  14 // FIXME: I didn't realise until later that `string' has a .Length method and so
  15 //        I am missing some proper bounds-checking in some methods. Find these
  16 //        instances and throw the ArgumentOutOfBoundsException at the programmer.
  17 //        I like pelting programmers with ArgumentOutOfBoundsException's :-)
  18
  19 // FIXME: The ToLower(), ToUpper(), and Compare(..., bool ignoreCase) methods
  20 //        need to be made unicode aware.
  21
  22 // FIXME: when you have a char carr[], does carr.Length include the terminating null char?
  23
  24 using System;
  25 using System.Text;
  26 using System.Collections;
  27 using System.Globalization;
  28 using System.Runtime.CompilerServices;
  29
  30 namespace System {
  31
  32         //[DefaultMemberName("Chars")]
  33         public sealed class String : IComparable, ICloneable, IConvertible, IEnumerable {
  34                 public static readonly string Empty = "";
  35                 private char[] c_str;
  36                 private int length;
  37
  38                 // Constructors
  39
  40                 internal String (int storage)
  41                 {
  42                         length = storage;
  43                         c_str = new char [storage];
  44                 }
  45
  46                 [CLSCompliant(false)]
  47                 unsafe public String (char *value)
  48                 {
  49                         int i;
  50
  51                         // FIXME: can I do value.Length here?
  52                         if (value == null) {
  53                                 this.length = 0;
  54                         } else {
  55                                 for (i = 0; *(value + i) != '\0'; i++);
  56                                 this.length = i;
  57                         }
  58
  59                         this.c_str = new char [this.length + 1];
  60                         for (i = 0; i < this.length; i++)
  61                                 this.c_str[i] = *(value + i);
  62                 }
  63
  64                 public String (char[] value)
  65                 {
  66                         int i;
  67
  68                         // FIXME: value.Length includes the terminating null char?
  69                         this.length = value != null ? strlen (value): 0;
  70                         this.c_str = new char [this.length + 1];
  71                         for (i = 0; i < this.length; i++)
  72                                 this.c_str[i] = value[i];
  73                 }
  74
  75                 [CLSCompliant(false)]
  76                 unsafe public String (sbyte *value)
  77                 {
  78                         // FIXME: consider unicode?
  79                         int i;
  80
  81                         // FIXME: can I do value.Length here? */
  82                         if (value == null) {
  83                                 this.length = 0;
  84                         } else {
  85                                 for (i = 0; *(value + i) != '\0'; i++);
  86                                 this.length = i;
  87                         }
  88
  89                         this.c_str = new char [this.length + 1];
  90                         for (i = 0; i < this.length; i++)
  91                                 this.c_str[i] = (char) *(value + i);
  92                 }
  93
  94                 public String (char c, int count)
  95                 {
  96                         int i;
  97
  98                         this.length = count;
  99                         this.c_str = new char [count + 1];
 100                         for (i = 0; i < count; i++)
 101                                 this.c_str[i] = c;
 102                 }
 103
 104                 [CLSCompliant(false)]
 105                 unsafe public String (char *value, int startIndex, int length)
 106                 {
 107                         int i;
 108
 109                         if (value == null && startIndex != 0 && length != 0)
 110                                 throw new ArgumentNullException ();
 111
 112                         if (startIndex < 0 || length < 0)
 113                                 throw new ArgumentOutOfRangeException ();
 114
 115                         this.length = length;
 116                         this.c_str = new char [length + 1];
 117                         for (i = 0; i < length; i++)
 118                                 this.c_str[i] = *(value + startIndex + i);
 119                 }
 120
 121                 public String (char[] value, int startIndex, int length)
 122                 {
 123                         int i;
 124
 125                         if (value == null && startIndex != 0 && length != 0)
 126                                 throw new ArgumentNullException ();
 127
 128                         if (startIndex < 0 || length < 0)
 129                                 throw new ArgumentOutOfRangeException ();
 130
 131                         this.length = length;
 132                         this.c_str = new char [length + 1];
 133                         for (i = 0; i < length; i++)
 134                                 this.c_str[i] = value[startIndex + i];
 135                 }
 136
 137                 [CLSCompliant(false)]
 138                 unsafe public String (sbyte *value, int startIndex, int length)
 139                 {
 140                         // FIXME: consider unicode?
 141                         int i;
 142
 143                         if (value == null && startIndex != 0 && length != 0)
 144                                 throw new ArgumentNullException ();
 145
 146                         if (startIndex < 0 || length < 0)
 147                                 throw new ArgumentOutOfRangeException ();
 148
 149                         this.length = length;
 150                         this.c_str = new char [length + 1];
 151                         for (i = 0; i < length; i++)
 152                                 this.c_str[i] = (char) *(value + startIndex + i);
 153                 }
 154
 155                 [CLSCompliant(false)][MonoTODO]
 156                 unsafe public String (sbyte *value, int startIndex, int length, Encoding enc)
 157                 {
 158                         // FIXME: implement me
 159                 }
 160
 161                 ~String ()
 162                 {
 163                         // FIXME: is there anything we need to do here?
 164                         /*base.Finalize ();*/
 165                 }
 166
 167                 // Properties
 168                 public int Length {
 169                         get {
 170                                 return this.length;
 171                         }
 172                 }
 173
 174                 [IndexerName("Chars")]
 175                 public char this [int index] {
 176                         get {
 177                                 if (index >= this.length)
 178                                         throw new ArgumentOutOfRangeException ();
 179
 180                                 return this.c_str[index];
 181                         }
 182                 }
 183
 184                 // Private helper methods
 185                 private static int strlen (char[] str)
 186                 {
 187                         // FIXME: if str.Length includes terminating null char, then return (str.Length - 1)
 188                         return str.Length;
 189                 }
 190
 191                 [MonoTODO]
 192                 private static char tolowerordinal (char c)
 193                 {
 194                         // FIXME: implement me
 195                         return c;
 196                 }
 197
 198                 private static bool is_lwsp (char c)
 199                 {
 200                         /* this comes from the msdn docs for String.Trim() */
 201                         if ((c >= '\x9' && c <= '\xD') || c == '\x20' || c == '\xA0' ||
 202                             (c >= '\x2000' && c <= '\x200B') || c == '\x3000' || c == '\xFEFF')
 203                                 return true;
 204                         else
 205                                 return false;
 206                 }
 207
 208                 private static int BoyerMoore (char[] haystack, string needle, int startIndex, int count)
 209                 {
 210                         /* (hopefully) Unicode-safe Boyer-Moore implementation */
 211                         int[] skiptable = new int[65536];  /* our unicode-safe skip-table */
 212                         int h, n, he, ne, hc, nc, i;
 213
 214                         if (haystack == null || needle == null)
 215                                 throw new ArgumentNullException ();
 216
 217                         /* if the search buffer is shorter than the pattern buffer, we can't match */
 218                         if (count < needle.length)
 219                                 return -1;
 220
 221                         /* return an instant match if the pattern is 0-length */
 222                         if (needle.length == 0)
 223                                 return startIndex;
 224
 225                         /* set a pointer at the end of each string */
 226                         ne = needle.length - 1;      /* position of char before '\0' */
 227                         he = startIndex + count;     /* position of last valid char */
 228
 229                         /* init the skip table with the pattern length */
 230                         nc = needle.length;
 231                         for (i = 0; i < 65536; i++)
 232                                 skiptable[i] = nc;
 233
 234                         /* set the skip value for the chars that *do* appear in the
 235                          * pattern buffer (needle) to the distance from the index to
 236                          * the end of the pattern buffer. */
 237                         for (nc = 0; nc < ne; nc++)
 238                                 skiptable[(int) needle[nc]] = ne - nc;
 239
 240                         h = startIndex;
 241                         while (count >= needle.length) {
 242                                 hc = h + needle.length - 1;  /* set the haystack compare pointer */
 243                                 nc = ne;                     /* set the needle compare pointer */
 244
 245                                 /* work our way backwards until they don't match */
 246                                 for (i = 0; nc > 0; nc--, hc--, i++)
 247                                         if (needle[nc] != haystack[hc])
 248                                                 break;
 249
 250                                 if (needle[nc] != haystack[hc]) {
 251                                         n = skiptable[(int) haystack[hc]] - i;
 252                                         h += n;
 253                                         count -= n;
 254                                 } else
 255                                         return h;
 256                         }
 257
 258                         return -1;
 259                 }
 260
 261                 // Methods
 262                 [MonoTODO]
 263                 public object Clone ()
 264                 {
 265                         // FIXME: implement me
 266                         return null;
 267                 }
 268
 269                 public static int Compare (string strA, string strB)
 270                 {
 271                         int min, i;
 272
 273                         if (strA == null) {
 274                                 if (strB == null)
 275                                         return 0;
 276                                 else
 277                                         return -1;
 278                         } else if (strB == null)
 279                                 return 1;
 280
 281                         min = strA.length < strB.length ? strA.length : strB.length;
 282
 283                         for (i = 0; i < min; i++) {
 284                                 if (strA.c_str[i] != strB.c_str[i]) {
 285                                         return (int)strA.c_str[i] - (int)strB.c_str[i];
 286                                 }
 287                         }
 288                         if (strA.length == strB.length) {
 289                                 return 0;
 290                         }
 291                         if (strA.length > min) {
 292                                 return 1;
 293                         } else {
 294                                 return -1;
 295                         }
 296                 }
 297
 298                 public static int Compare (string strA, string strB, bool ignoreCase)
 299                 {
 300                         int min, i;
 301
 302                         if (!ignoreCase)
 303                                 return Compare (strA, strB);
 304
 305                         /*
 306                          * And here I thought Eazel developers were on crack...
 307                          * if a string is null it should pelt the programmer with
 308                          * ArgumentNullExceptions, damnit!
 309                          */
 310                         if (strA == null) {
 311                                 if (strB == null)
 312                                         return 0;
 313                                 else
 314                                         return -1;
 315                         } else if (strB == null)
 316                                 return 1;
 317
 318                         min = strA.length < strB.length ? strA.length : strB.length;
 319
 320                         for (i = 0; i < min; i++) {
 321                                 if (Char.ToLower (strA.c_str[i]) != Char.ToLower (strB.c_str[i]))
 322                                         break;
 323                         }
 324
 325                         return ((int) (strA.c_str[i] - strB.c_str[i]));
 326                 }
 327
 328                 [MonoTODO]
 329                 public static int Compare (string strA, string strB, bool ignoreCase, CultureInfo culture)
 330                 {
 331                         // FIXME: implement me
 332                         return 0;
 333                 }
 334
 335                 public static int Compare (string strA, int indexA, string strB, int indexB, int length)
 336                 {
 337                         int i;
 338
 339                         if (length < 0 || indexA < 0 || indexB < 0)
 340                                 throw new ArgumentOutOfRangeException ();
 341
 342                         if (indexA > strA.Length || indexB > strB.Length)
 343                                 throw new ArgumentOutOfRangeException ();
 344
 345                         /* And again with the ("" > null) logic... lord have mercy! */
 346                         if (strA == null) {
 347                                 if (strB == null)
 348                                         return 0;
 349                                 else
 350                                         return -1;
 351                         } else if (strB == null)
 352                                 return 1;
 353
 354                         for (i = 0; i < length - 1; i++) {
 355                                 if (strA[indexA + i] != strB[indexB + i])
 356                                         break;
 357                         }
 358
 359                         return ((int) (strA[indexA + i] - strB[indexB + i]));
 360                 }
 361
 362                 public static int Compare (string strA, int indexA, string strB, int indexB,
 363                                            int length, bool ignoreCase)
 364                 {
 365                         int i;
 366
 367                         if (!ignoreCase)
 368                                 return Compare (strA, indexA, strB, indexB, length);
 369
 370                         if (length < 0 || indexA < 0 || indexB < 0)
 371                                 throw new ArgumentOutOfRangeException ();
 372
 373                         if (indexA > strA.Length || indexB > strB.Length)
 374                                 throw new ArgumentOutOfRangeException ();
 375
 376                         /* When will the hurting stop!?!? */
 377                         if (strA == null) {
 378                                 if (strB == null)
 379                                         return 0;
 380                                 else
 381                                         return -1;
 382                         } else if (strB == null)
 383                                 return 1;
 384
 385                         for (i = 0; i < length - 1; i++) {
 386                                 if (Char.ToLower (strA[indexA + i]) != Char.ToLower (strB[indexB + i]))
 387                                         break;
 388                         }
 389
 390                         return ((int) (strA[indexA + i] - strB[indexB + i]));
 391                 }
 392
 393                 [MonoTODO]
 394                 public static int Compare (string strA, int indexA, string strB, int indexB,
 395                                            int length, bool ignoreCase, CultureInfo culture)
 396                 {
 397                         if (culture == null)
 398                                 throw new ArgumentNullException ();
 399
 400                         if (length < 0 || indexA < 0 || indexB < 0)
 401                                 throw new ArgumentOutOfRangeException ();
 402
 403                         if (indexA > strA.Length || indexB > strB.Length)
 404                                 throw new ArgumentOutOfRangeException ();
 405
 406                         /* I can't take it anymore! */
 407                         if (strA == null) {
 408                                 if (strB == null)
 409                                         return 0;
 410                                 else
 411                                         return -1;
 412                         } else if (strB == null)
 413                                 return 1;
 414
 415                         // FIXME: implement me
 416                         return 0;
 417                 }
 418
 419                 public static int CompareOrdinal (string strA, string strB)
 420                 {
 421                         int i;
 422
 423                         /* Please God, make it stop! */
 424                         if (strA == null) {
 425                                 if (strB == null)
 426                                         return 0;
 427                                 else
 428                                         return -1;
 429                         } else if (strB == null)
 430                                 return 1;
 431
 432                         for (i = 0; i < strA.Length && i < strB.Length; i++) {
 433                                 char cA, cB;
 434
 435                                 cA = tolowerordinal (strA[i]);
 436                                 cB = tolowerordinal (strB[i]);
 437
 438                                 if (cA != cB)
 439                                         break;
 440                         }
 441
 442                         return ((int) (strA[i] - strB[i]));
 443                 }
 444
 445                 public static int CompareOrdinal (string strA, int indexA, string strB, int indexB,
 446                                                   int length)
 447                 {
 448                         int i;
 449
 450                         if (length < 0 || indexA < 0 || indexB < 0)
 451                                 throw new ArgumentOutOfRangeException ();
 452
 453                         if (strA == null) {
 454                                 if (strB == null)
 455                                         return 0;
 456                                 else
 457                                         return -1;
 458                         } else if (strB == null)
 459                                 return 1;
 460
 461                         for (i = 0; i < length; i++) {
 462                                 char cA, cB;
 463
 464                                 cA = tolowerordinal (strA[indexA + i]);
 465                                 cB = tolowerordinal (strB[indexB + i]);
 466
 467                                 if (cA != cB)
 468                                         break;
 469                         }
 470
 471                         return ((int) (strA[indexA + i] - strB[indexB + i]));
 472                 }
 473
 474                 public int CompareTo (object obj)
 475                 {
 476                         return Compare (this, obj == null ? null : obj.ToString ());
 477                 }
 478
 479                 public int CompareTo (string str)
 480                 {
 481                         return Compare (this, str);
 482                 }
 483
 484                 public static string Concat (object arg)
 485                 {
 486                         return arg != null ? arg.ToString () : String.Empty;
 487                 }
 488
 489                 public static string Concat (params object[] args)
 490                 {
 491                         string[] strings;
 492                         char[] str;
 493                         int len, i;
 494
 495                         if (args == null)
 496                                 throw new ArgumentNullException ();
 497
 498                         strings = new string [args.Length];
 499                         len = 0;
 500                         i = 0;
 501                         foreach (object arg in args) {
 502                                 /* use Empty for each null argument */
 503                                 if (arg == null)
 504                                         strings[i] = String.Empty;
 505                                 else
 506                                         strings[i] = arg.ToString ();
 507                                 len += strings[i].length;
 508                                 i++;
 509                         }
 510
 511                         if (len == 0)
 512                                 return String.Empty;
 513
 514                         String res = new String (len);
 515                         str = res.c_str;
 516                         i = 0;
 517                         for (int j = 0; j < strings.Length; j++)
 518                                 for (int k = 0; k < strings[j].length; k++)
 519                                         str[i++] = strings[j].c_str[k];
 520
 521                         return res;
 522                 }
 523
 524                 public static string Concat (params string[] values)
 525                 {
 526                         int len, i;
 527                         char[] str;
 528
 529                         if (values == null)
 530                                 throw new ArgumentNullException ();
 531
 532                         len = 0;
 533                         foreach (string value in values)
 534                                 len += value != null ? value.Length : 0;
 535
 536                         if (len == 0)
 537                                 return String.Empty;
 538
 539                         String res = new String (len);
 540                         str = res.c_str;
 541                         i = 0;
 542                         foreach (string value in values) {
 543                                 if (value == null)
 544                                         continue;
 545
 546                                 for (int j = 0; j < value.length; j++)
 547                                         str[i++] = value.c_str[j];
 548                         }
 549
 550                         return res;
 551                 }
 552
 553                 public static string Concat (object arg0, object arg1)
 554                 {
 555                         string str0 = arg0 != null ? arg0.ToString () : String.Empty;
 556                         string str1 = arg1 != null ? arg1.ToString () : String.Empty;
 557
 558                         return Concat (str0, str1);
 559                 }
 560
 561                 public static string Concat (string str0, string str1)
 562                 {
 563                         char[] concat;
 564                         int i, j, len;
 565
 566                         if (str0 == null)
 567                                 str0 = String.Empty;
 568                         if (str1 == null)
 569                                 str1 = String.Empty;
 570
 571                         len = str0.length + str1.length;
 572                         if (len == 0)
 573                                 return String.Empty;
 574
 575                         String res = new String (len);
 576
 577                         concat = res.c_str;
 578                         for (i = 0; i < str0.length; i++)
 579                                 concat[i] = str0.c_str[i];
 580                         for (j = 0 ; j < str1.length; j++)
 581                                 concat[i + j] = str1.c_str[j];
 582
 583                         return res;
 584                 }
 585
 586                 public static string Concat (object arg0, object arg1, object arg2)
 587                 {
 588                         string str0 = arg0 != null ? arg0.ToString () : String.Empty;
 589                         string str1 = arg1 != null ? arg1.ToString () : String.Empty;
 590                         string str2 = arg2 != null ? arg2.ToString () : String.Empty;
 591
 592                         return Concat (str0, str1, str2);
 593                 }
 594
 595                 public static string Concat (string str0, string str1, string str2)
 596                 {
 597                         char[] concat;
 598                         int i, j, k, len;
 599
 600                         if (str0 == null)
 601                                 str0 = String.Empty;
 602                         if (str1 == null)
 603                                 str1 = String.Empty;
 604                         if (str2 == null)
 605                                 str2 = String.Empty;
 606
 607                         len = str0.length + str1.length + str2.length;
 608                         if (len == 0)
 609                                 return String.Empty;
 610
 611                         String res = new String (len);
 612
 613                         concat = res.c_str;
 614                         for (i = 0; i < str0.length; i++)
 615                                 concat[i] = str0.c_str[i];
 616                         for (j = 0; j < str1.length; j++)
 617                                 concat[i + j] = str1.c_str[j];
 618                         for (k = 0; k < str2.length; k++)
 619                                 concat[i + j + k] = str2.c_str[k];
 620
 621                         return res;
 622                 }
 623
 624                 public static string Concat (string str0, string str1, string str2, string str3)
 625                 {
 626                         char[] concat;
 627                         int i, j, k, l, len;
 628
 629                         if (str0 == null)
 630                                 str0 = String.Empty;
 631                         if (str1 == null)
 632                                 str1 = String.Empty;
 633                         if (str2 == null)
 634                                 str2 = String.Empty;
 635                         if (str3 == null)
 636                                 str3 = String.Empty;
 637
 638                         len = str0.length + str1.length + str2.length + str3.length;
 639                         if (len == 0)
 640                                 return String.Empty;
 641                         String res = new String (len);
 642
 643                         concat = res.c_str;
 644                         for (i = 0; i < str0.length; i++)
 645                                 concat[i] = str0.c_str[i];
 646                         for (j = 0; j < str1.length; j++)
 647                                 concat[i + j] = str1.c_str[j];
 648                         for (k = 0; k < str2.length; k++)
 649                                 concat[i + j + k] = str2.c_str[k];
 650                         for (l = 0; l < str3.length; l++)
 651                                 concat[i + j + k + l] = str3.c_str[l];
 652
 653                         return res;
 654                 }
 655
 656                 public static string Copy (string str)
 657                 {
 658                         // FIXME: how do I *copy* a string if I can only have 1 of each?
 659                         if (str == null)
 660                                 throw new ArgumentNullException ();
 661
 662                         return str;
 663                 }
 664
 665                 public void CopyTo (int sourceIndex, char[] destination, int destinationIndex, int count)
 666                 {
 667                         // LAMESPEC: should I null-terminate?
 668                         int i;
 669
 670                         if (destination == null)
 671                                 throw new ArgumentNullException ();
 672
 673                         if (sourceIndex < 0 || destinationIndex < 0 || count < 0)
 674                                 throw new ArgumentOutOfRangeException ();
 675
 676                         if (sourceIndex + count > this.length)
 677                                 throw new ArgumentOutOfRangeException ();
 678
 679                         if (destinationIndex + count > destination.Length)
 680                                 throw new ArgumentOutOfRangeException ();
 681
 682                         for (i = 0; i < count; i++)
 683                                 destination[destinationIndex + i] = this.c_str[sourceIndex + i];
 684                 }
 685
 686                 public bool EndsWith (string value)
 687                 {
 688                         bool endswith = true;
 689                         int start, i;
 690
 691                         if (value == null)
 692                                 throw new ArgumentNullException ();
 693
 694                         start = this.length - value.length;
 695                         if (start < 0)
 696                                 return false;
 697
 698                         for (i = start; i < this.length && endswith; i++)
 699                                 endswith = this.c_str[i] == value.c_str[i - start];
 700
 701                         return endswith;
 702                 }
 703
 704                 public override bool Equals (object obj)
 705                 {
 706                         if (!(obj is String))
 707                                 return false;
 708
 709                         return this == (String) obj;
 710                 }
 711
 712                 public bool Equals (string value)
 713                 {
 714                         return this == value;
 715                 }
 716
 717                 public static bool Equals (string a, string b)
 718                 {
 719                         return a == b;
 720                 }
 721
 722                 [MonoTODO]
 723                 public static string Format (string format, object arg0)
 724                 {
 725                         // FIXME: implement me
 726                         return format+arg0.ToString();
 727                 }
 728
 729                 [MonoTODO]
 730                 public static string Format (string format, params object[] args)
 731                 {
 732                         // FIXME: implement me
 733                         Console.WriteLine (args[0].ToString());
 734                         if (args.Length == 1)
 735                                 return format+args[0].ToString();
 736                         if (args.Length == 2)
 737                                 return format+args[0].ToString()+args[1].ToString();
 738                         if (args.Length == 3)
 739                                 return format+args[0].ToString()+args[1].ToString()+args[2].ToString();
 740                         if (args.Length == 4)
 741                                 return format+args[0].ToString()+args[1].ToString()+args[2].ToString()+args[3].ToString();
 742                         Console.WriteLine ("String.Format with args: "+args.Length.ToString());
 743                         return format;
 744                 }
 745
 746                 [MonoTODO]
 747                 public static string Format (IFormatProvider provider, string format, params object[] args)
 748                 {
 749                         // FIXME: implement me
 750                         return null;
 751                 }
 752
 753                 [MonoTODO]
 754                 public static string Format (string format, object arg0, object arg1)
 755                 {
 756                         // FIXME: implement me
 757                         return format+arg0.ToString()+arg1.ToString();
 758                 }
 759
 760                 [MonoTODO]
 761                 public static string Format (string format, object arg0, object arg1, object arg2)
 762                 {
 763                         // FIXME: implement me
 764                         return format+arg0.ToString()+arg1.ToString()+arg2.ToString();
 765                 }
 766
 767                 //public CharEnumerator GetEnumerator ()
 768                 [MonoTODO]
 769                 public IEnumerator GetEnumerator ()
 770                 {
 771                         // FIXME: implement me
 772                         return null;
 773                 }
 774
 775                 public override int GetHashCode ()
 776                 {
 777                         int h = 0;
 778                         int i;
 779                         for (i = 0; i < length; ++i)
 780                                 h = (h << 5) - h + c_str [i];
 781                         return h;
 782                 }
 783
 784                 public TypeCode GetTypeCode ()
 785                 {
 786                         return TypeCode.String;
 787                 }
 788
 789                 public int IndexOf (char value)
 790                 {
 791                         return IndexOf (value, 0, this.length);
 792                 }
 793
 794                 public int IndexOf (string value)
 795                 {
 796                         return IndexOf (value, 0, this.length);
 797                 }
 798
 799                 public int IndexOf (char value, int startIndex)
 800                 {
 801                         return IndexOf (value, startIndex, this.length - startIndex);
 802                 }
 803
 804                 public int IndexOf (string value, int startIndex)
 805                 {
 806                         return IndexOf (value, startIndex, this.length - startIndex);
 807                 }
 808
 809                 public int IndexOf (char value, int startIndex, int count)
 810                 {
 811                         int i;
 812
 813                         if (startIndex < 0 || count < 0 || startIndex + count > this.length)
 814                                 throw new ArgumentOutOfRangeException ();
 815
 816                         for (i = startIndex; i - startIndex < count; i++)
 817                                 if (this.c_str[i] == value)
 818                                         return i;
 819
 820                         return -1;
 821                 }
 822
 823                 public int IndexOf (string value, int startIndex, int count)
 824                 {
 825                         if (value == null)
 826                                 throw new ArgumentNullException ();
 827
 828                         if (startIndex < 0 || count < 0 || startIndex + count > this.length)
 829                                 throw new ArgumentOutOfRangeException ();
 830
 831                         return BoyerMoore (this.c_str, value, startIndex, count);
 832 #if XXX
 833                         int i;
 834                         for (i = startIndex; i - startIndex + value.Length <= count; ) {
 835                                 if (this.c_str[i] == value[0]) {
 836                                         bool equal = true;
 837                                         int j, nexti = 0;
 838
 839                                         for (j = 1; equal && j < value.Length; j++) {
 840                                                 equal = this.c_str[i + j] == value[j];
 841                                                 if (this.c_str[i + j] == value[0] && nexti == 0)
 842                                                         nexti = i + j;
 843                                         }
 844
 845                                         if (equal)
 846                                                 return i;
 847
 848                                         if (nexti != 0)
 849                                                 i = nexti;
 850                                         else
 851                                                 i += j;
 852                                 } else
 853                                         i++;
 854                         }
 855
 856                         return -1;
 857 #endif
 858                 }
 859
 860                 public int IndexOfAny (char[] values)
 861                 {
 862                         return IndexOfAny (values, 0, this.length);
 863                 }
 864
 865                 public int IndexOfAny (char[] values, int startIndex)
 866                 {
 867                         return IndexOfAny (values, startIndex, this.length - startIndex);
 868                 }
 869
 870                 public int IndexOfAny (char[] values, int startIndex, int count)
 871                 {
 872                         if (values == null)
 873                                 throw new ArgumentNullException ();
 874
 875                         if (startIndex < 0 || count < 0 || startIndex + count > this.length)
 876                                 throw new ArgumentOutOfRangeException ();
 877
 878                         for (int i = startIndex; i < startIndex + count; i++) {
 879                                 for (int j = 0; j < strlen (values); j++) {
 880                                         if (this.c_str[i] == values[j])
 881                                                 return i;
 882                                 }
 883                         }
 884
 885                         return -1;
 886                 }
 887
 888                 public string Insert (int startIndex, string value)
 889                 {
 890                         char[] str;
 891                         int i, j;
 892
 893                         if (value == null)
 894                                 throw new ArgumentNullException ();
 895
 896                         if (startIndex < 0 || startIndex > this.length)
 897                                 throw new ArgumentOutOfRangeException ();
 898
 899                         String res = new String (value.length + this.length);
 900
 901                         str = res.c_str;
 902                         for (i = 0; i < startIndex; i++)
 903                                 str[i] = this.c_str[i];
 904                         for (j = 0; j < value.length; j++)
 905                                 str[i + j] = value.c_str[j];
 906                         for ( ; i < this.length; i++)
 907                                 str[i + j] = this.c_str[i];
 908
 909                         return res;
 910                 }
 911
 912                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 913                 public extern static string Intern (string str);
 914
 915                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
 916                 public extern static string IsInterned (string str);
 917
 918                 public static string Join (string separator, string[] value)
 919                 {
 920                         return Join (separator, value, 0, value.Length);
 921                 }
 922
 923                 public static string Join (string separator, string[] value, int startIndex, int count)
 924                 {
 925                         // LAMESPEC: msdn doesn't specify what happens when separator is null
 926                         int len, i, j, used;
 927                         char[] str;
 928
 929                         if (separator == null || value == null)
 930                                 throw new ArgumentNullException ();
 931
 932                         if (startIndex + count > value.Length)
 933                                 throw new ArgumentOutOfRangeException ();
 934
 935                         len = 0;
 936                         for (i = startIndex, used = 0; used < count; i++, used++) {
 937                                 if (i != startIndex)
 938                                         len += separator.length;
 939
 940                                 len += value[i].length;
 941                         }
 942
 943                         // We have no elements to join?
 944                         if (i == startIndex)
 945                                 return String.Empty;
 946
 947                         String res = new String (len);
 948
 949                         str = res.c_str;
 950                         for (i = 0; i < value[startIndex].length; i++)
 951                                 str[i] = value[startIndex][i];
 952
 953                         used = 1;
 954                         for (j = startIndex + 1; used < count; j++, used++) {
 955                                 int k;
 956
 957                                 for (k = 0; k < separator.length; k++)
 958                                         str[i++] = separator.c_str[k];
 959                                 for (k = 0; k < value[j].length; k++)
 960                                         str[i++] = value[j].c_str[k];
 961                         }
 962
 963                         return res;
 964                 }
 965
 966                 public int LastIndexOf (char value)
 967                 {
 968                         int i = this.length;
 969                         if (i == 0)
 970                                 return -1;
 971                         --i;
 972                         for (; i >= 0; i--) {
 973                                 if (this.c_str[i] == value)
 974                                         return i;
 975                         }
 976
 977                         return -1;
 978                 }
 979
 980                 public int LastIndexOf (string value)
 981                 {
 982                         return LastIndexOf (value, this.length - 1, this.length);
 983                 }
 984
 985                 public int LastIndexOf (char value, int startIndex)
 986                 {
 987                         if (startIndex < 0 || startIndex >= this.length)
 988                                 throw new ArgumentOutOfRangeException ();
 989
 990                         for (int i = startIndex; i >= 0; i--) {
 991                                 if (this.c_str[i] == value)
 992                                         return i;
 993                         }
 994
 995                         return -1;
 996                 }
 997
 998                 public int LastIndexOf (string value, int startIndex)
 999                 {
1000                         return LastIndexOf (value, startIndex, startIndex + 1);
1001                 }
1002
1003                 public int LastIndexOf (char value, int startIndex, int count)
1004                 {
1005                         if (startIndex < 0 || count < 0)
1006                                 throw new ArgumentOutOfRangeException ();
1007
1008                         if (startIndex >= this.length || startIndex - count + 1 < 0)
1009                                 throw new ArgumentOutOfRangeException ();
1010
1011                         for (int i = startIndex; i > startIndex - count; i--) {
1012                                 if (this.c_str[i] == value)
1013                                         return i;
1014                         }
1015
1016                         return -1;
1017                 }
1018
1019                 public int LastIndexOf (string value, int startIndex, int count)
1020                 {
1021                         // LAMESPEC: currently I'm using startIndex as the 0-position in the comparison,
1022                         //           but maybe it's the end-position in MS's implementation?
1023                         //           msdn is unclear on this point. I think this is correct though.
1024                         int i, len;
1025
1026                         if (value == null)
1027                                 throw new ArgumentNullException ();
1028
1029                         if (startIndex < 0 || startIndex >= this.length)
1030                                 throw new ArgumentOutOfRangeException ();
1031
1032                         if (count < 0 || startIndex - count + 1 < 0)
1033                                 throw new ArgumentOutOfRangeException ();
1034
1035                         if (value == String.Empty)
1036                                 return startIndex;
1037
1038                         if (startIndex + value.length > this.length) {
1039                                 /* just a little optimization */
1040                                 int start;
1041
1042                                 start = this.length - value.length;
1043                                 count -= startIndex - start;
1044                                 startIndex = start;
1045                         }
1046
1047                         // FIXME: use a reversed-unicode-safe-Boyer-Moore?
1048                         len = value.length - 1;
1049                         for (i = startIndex; i > startIndex - count; i--) {
1050                                 if (this.c_str[i + len] == value.c_str[len]) {
1051                                         bool equal = true;
1052                                         int j;
1053
1054                                         for (j = len - 1; equal && j >= 0; j--)
1055                                                 equal = this.c_str[i + j] == value.c_str[j];
1056
1057                                         if (equal)
1058                                                 return i;
1059                                 }
1060                         }
1061
1062                         return -1;
1063                 }
1064
1065                 public int LastIndexOfAny (char[] values)
1066                 {
1067                         return LastIndexOfAny (values, this.length - 1, this.length);
1068                 }
1069
1070                 public int LastIndexOfAny (char[] values, int startIndex)
1071                 {
1072                         return LastIndexOfAny (values, startIndex, startIndex + 1);
1073                 }
1074
1075                 public int LastIndexOfAny (char[] values, int startIndex, int count)
1076                 {
1077                         int i;
1078
1079                         if (values == null)
1080                                 throw new ArgumentNullException ();
1081
1082                         if (startIndex < 0 || count < 0 || startIndex - count + 1 < 0)
1083                                 throw new ArgumentOutOfRangeException ();
1084
1085                         for (i = startIndex; i > startIndex - count; i--) {
1086                                 for (int j = 0; j < strlen (values); j++) {
1087                                         if (this.c_str[i] == values[j])
1088                                                 return i;
1089                                 }
1090                         }
1091
1092                         return -1;
1093                 }
1094
1095                 public string PadLeft (int totalWidth)
1096                 {
1097                         return PadLeft (totalWidth, ' ');
1098                 }
1099
1100                 public string PadLeft (int totalWidth, char padChar)
1101                 {
1102                         char[] str;
1103                         int i, j;
1104
1105                         if (totalWidth < 0)
1106                                 throw new ArgumentException ();
1107
1108                         str = new char [totalWidth > this.length ? totalWidth : this.length];
1109                         for (i = 0; i < totalWidth - this.length; i++)
1110                                 str[i] = padChar;
1111
1112                         for (j = 0; j < this.length; i++, j++)
1113                                 str[i] = this.c_str[j];
1114
1115                         return new String (str);
1116                 }
1117
1118                 public string PadRight (int totalWidth)
1119                 {
1120                         return PadRight (totalWidth, ' ');
1121                 }
1122
1123                 public string PadRight (int totalWidth, char padChar)
1124                 {
1125                         char[] str;
1126                         int i;
1127
1128                         if (totalWidth < 0)
1129                                 throw new ArgumentException ();
1130
1131                         str = new char [totalWidth > this.length ? totalWidth : this.length];
1132                         for (i = 0; i < this.length; i++)
1133                                 str[i] = this.c_str[i];
1134
1135                         for ( ; i < str.Length; i++)
1136                                 str[i] = padChar;
1137
1138                         return new String (str);
1139                 }
1140
1141                 public string Remove (int startIndex, int count)
1142                 {
1143                         char[] str;
1144                         int i, j, len;
1145
1146                         if (startIndex < 0 || count < 0 || startIndex + count > this.length)
1147                                 throw new ArgumentOutOfRangeException ();
1148
1149                         len = this.length - count;
1150                         if (len == 0)
1151                                 return String.Empty;
1152
1153                         String res = new String (len);
1154                         str = res.c_str;
1155                         for (i = 0; i < startIndex; i++)
1156                                 str[i] = this.c_str[i];
1157                         for (j = i + count; j < this.length; j++)
1158                                 str[i++] = this.c_str[j];
1159
1160                         return res;
1161                 }
1162
1163                 public string Replace (char oldChar, char newChar)
1164                 {
1165                         char[] str;
1166                         int i;
1167
1168                         String res = new String (length);
1169                         str = res.c_str;
1170                         for (i = 0; i < this.length; i++) {
1171                                 if (this.c_str[i] == oldChar)
1172                                         str[i] = newChar;
1173                                 else
1174                                         str[i] = this.c_str[i];
1175                         }
1176
1177                         return res;
1178                 }
1179
1180                 public string Replace (string oldValue, string newValue)
1181                 {
1182                         // LAMESPEC: msdn doesn't specify what to do if either args is null
1183                         int index, len, i, j;
1184                         char[] str;
1185
1186                         if (oldValue == null || newValue == null)
1187                                 throw new ArgumentNullException ();
1188
1189                         // Use IndexOf in case I later rewrite it to use Boyer-Moore
1190                         index = IndexOf (oldValue, 0);
1191                         if (index == -1) {
1192                                 // This is the easy one ;-)
1193                                 return Substring (0, this.length);
1194                         }
1195
1196                         len = this.length - oldValue.length + newValue.length;
1197                         if (len == 0)
1198                                 return String.Empty;
1199
1200                         String res = new String (len);
1201                         str = res.c_str;
1202                         for (i = 0; i < index; i++)
1203                                 str[i] = this.c_str[i];
1204                         for (j = 0; j < newValue.length; j++)
1205                                 str[i++] = newValue[j];
1206                         for (j = index + oldValue.length; j < this.length; j++)
1207                                 str[i++] = this.c_str[j];
1208
1209                         return res;
1210                 }
1211
1212                 private int splitme (char[] separators, int startIndex)
1213                 {
1214                         /* this is basically a customized IndexOfAny() for the Split() methods */
1215                         for (int i = startIndex; i < this.length; i++) {
1216                                 if (separators != null) {
1217                                         foreach (char sep in separators) {
1218                                                 if (this.c_str[i] == sep)
1219                                                         return i - startIndex;
1220                                         }
1221                                 } else if (is_lwsp (this.c_str[i])) {
1222                                         return i - startIndex;
1223                                 }
1224                         }
1225
1226                         return -1;
1227                 }
1228
1229                 public string[] Split (params char[] separator)
1230                 {
1231                         /**
1232                          * split:
1233                          * @separator: delimiting chars or null to split on whtspc
1234                          *
1235                          * Returns: 1. An array consisting of a single
1236                          * element (@this) if none of the delimiting
1237                          * chars appear in @this. 2. An array of
1238                          * substrings which are delimited by one of
1239                          * the separator chars. 3. An array of
1240                          * substrings separated by whitespace if
1241                          * @separator is null. The Empty string should
1242                          * be returned wherever 2 delimiting chars are
1243                          * adjacent.
1244                          **/
1245                         // FIXME: would using a Queue be better?
1246                         string[] strings;
1247                         ArrayList list;
1248                         int index, len;
1249
1250                         list = new ArrayList ();
1251                         for (index = 0, len = 0; index < this.length; index += len + 1) {
1252                                 len = splitme (separator, index);
1253                                 len = len > -1 ? len : this.length - index;
1254                                 if (len == 0) {
1255                                         list.Add (String.Empty);
1256                                 } else {
1257                                         char[] str;
1258                                         int i;
1259
1260                                         str = new char [len];
1261                                         for (i = 0; i < len; i++)
1262                                                 str[i] = this.c_str[index + i];
1263
1264                                         list.Add (new String (str));
1265                                 }
1266                         }
1267
1268                         strings = new string [list.Count];
1269                         if (list.Count == 1) {
1270                                 /* special case for an array holding @this */
1271                                 strings[0] = this;
1272                         } else {
1273                                 for (index = 0; index < list.Count; index++)
1274                                         strings[index] = (string) list[index];
1275                         }
1276
1277                         return strings;
1278                 }
1279
1280                 public string[] Split (char[] separator, int maxCount)
1281                 {
1282                         // FIXME: what to do if maxCount <= 0?
1283                         // FIXME: would using Queue be better than ArrayList?
1284                         string[] strings;
1285                         ArrayList list;
1286                         int index, len, used;
1287
1288                         used = 0;
1289                         list = new ArrayList ();
1290                         for (index = 0, len = 0; index < this.length && used < maxCount; index += len + 1) {
1291                                 len = splitme (separator, index);
1292                                 len = len > -1 ? len : this.length - index;
1293                                 if (len == 0) {
1294                                         list.Add (String.Empty);
1295                                 } else {
1296                                         char[] str;
1297                                         int i;
1298
1299                                         str = new char [len];
1300                                         for (i = 0; i < len; i++)
1301                                                 str[i] = this.c_str[index + i];
1302
1303                                         list.Add (new String (str));
1304                                 }
1305                                 used++;
1306                         }
1307
1308                         /* fit the remaining chunk of the @this into it's own element */
1309                         if (index != this.length) {
1310                                 char[] str;
1311                                 int i;
1312
1313                                 str = new char [this.length - index];
1314                                 for (i = index; i < this.length; i++)
1315                                         str[i - index] = this.c_str[i];
1316
1317                                 list.Add (new String (str));
1318                         }
1319
1320                         strings = new string [list.Count];
1321                         if (list.Count == 1) {
1322                                 /* special case for an array holding @this */
1323                                 strings[0] = this;
1324                         } else {
1325                                 for (index = 0; index < list.Count; index++)
1326                                         strings[index] = (string) list[index];
1327                         }
1328
1329                         return strings;
1330                 }
1331
1332                 public bool StartsWith (string value)
1333                 {
1334                         bool startswith = true;
1335                         int i;
1336
1337                         if (value == null)
1338                                 throw new ArgumentNullException ();
1339
1340                         if (value.length > this.length)
1341                                 return false;
1342
1343                         for (i = 0; i < value.length && startswith; i++)
1344                                 startswith = startswith && value.c_str[i] == this.c_str[i];
1345
1346                         return startswith;
1347                 }
1348
1349                 public string Substring (int startIndex)
1350                 {
1351                         char[] str;
1352                         int i, len;
1353
1354                         if (startIndex < 0 || startIndex > this.length)
1355                                 throw new ArgumentOutOfRangeException ();
1356
1357                         len = this.length - startIndex;
1358                         if (len == 0)
1359                                 return String.Empty;
1360                         String res = new String (len);
1361                         str = res.c_str;
1362                         for (i = startIndex; i < this.length; i++)
1363                                 str[i - startIndex] = this.c_str[i];
1364
1365                         return res;
1366                 }
1367
1368                 public string Substring (int startIndex, int length)
1369                 {
1370                         char[] str;
1371                         int i;
1372
1373                         if (startIndex < 0 || length < 0 || startIndex + length > this.length)
1374                                 throw new ArgumentOutOfRangeException ();
1375
1376                         if (length == 0)
1377                                 return String.Empty;
1378
1379                         String res = new String (length);
1380                         str = res.c_str;
1381                         for (i = startIndex; i < startIndex + length; i++)
1382                                 str[i - startIndex] = this.c_str[i];
1383
1384                         return res;
1385                 }
1386
1387                 [MonoTODO]
1388                 public bool ToBoolean (IFormatProvider provider)
1389                 {
1390                         // FIXME: implement me
1391                         throw new NotImplementedException ();
1392                 }
1393
1394                 [MonoTODO]
1395                 public byte ToByte (IFormatProvider provider)
1396                 {
1397                         // FIXME: implement me
1398                         throw new NotImplementedException ();
1399                 }
1400
1401                 [MonoTODO]
1402                 public char ToChar (IFormatProvider provider)
1403                 {
1404                         // FIXME: implement me
1405                         throw new NotImplementedException ();
1406                 }
1407
1408                 public char[] ToCharArray ()
1409                 {
1410                         return ToCharArray (0, this.length);
1411                 }
1412
1413                 public char[] ToCharArray (int startIndex, int length)
1414                 {
1415                         char[] chars;
1416                         int i;
1417
1418                         if (startIndex < 0 || length < 0 || startIndex + length > this.length)
1419                                 throw new ArgumentOutOfRangeException ();
1420
1421                         chars = new char [length];
1422                         for (i = startIndex; i < length; i++)
1423                                 chars[i - startIndex] = this.c_str[i];
1424
1425                         return chars;
1426                 }
1427
1428                 [MonoTODO]
1429                 public DateTime ToDateTime (IFormatProvider provider)
1430                 {
1431                         // FIXME: implement me
1432                         // return new DateTime (0);
1433                         throw new NotImplementedException ();
1434                 }
1435
1436                 [MonoTODO]
1437                 public decimal ToDecimal (IFormatProvider provider)
1438                 {
1439                         // FIXME: implement me
1440                         throw new NotImplementedException ();
1441                 }
1442
1443                 [MonoTODO]
1444                 public double ToDouble (IFormatProvider provider)
1445                 {
1446                         // FIXME: implement me
1447                         throw new NotImplementedException ();
1448                 }
1449
1450                 [MonoTODO]
1451                 public short ToInt16 (IFormatProvider provider)
1452                 {
1453                         // FIXME: implement me
1454                         throw new NotImplementedException ();
1455                 }
1456
1457                 [MonoTODO]
1458                 public int ToInt32 (IFormatProvider provider)
1459                 {
1460                         // FIXME: implement me
1461                         throw new NotImplementedException ();
1462                 }
1463
1464                 [MonoTODO]
1465                 public long ToInt64 (IFormatProvider provider)
1466                 {
1467                         // FIXME: implement me
1468                         throw new NotImplementedException ();
1469                 }
1470
1471                 public string ToLower ()
1472                 {
1473                         char[] str;
1474                         int i;
1475
1476                         String res = new String (length);
1477                         str = res.c_str;
1478                         for (i = 0; i < this.length; i++)
1479                                 str[i] = Char.ToLower (this.c_str[i]);
1480
1481                         return res;
1482                 }
1483
1484                 [MonoTODO]
1485                 public string ToLower (CultureInfo culture)
1486                 {
1487                         // FIXME: implement me
1488                         throw new NotImplementedException ();
1489
1490                 }
1491
1492                 [CLSCompliant(false)][MonoTODO]
1493                 public sbyte ToSByte (IFormatProvider provider)
1494                 {
1495                         // FIXME: implement me
1496                         throw new NotImplementedException ();
1497                 }
1498
1499                 [MonoTODO]
1500                 public float ToSingle (IFormatProvider provider)
1501                 {
1502                         // FIXME: implement me
1503                         throw new NotImplementedException ();
1504                 }
1505
1506                 public override string ToString ()
1507                 {
1508                         return this;
1509                 }
1510
1511                 [MonoTODO]
1512                 public string ToString (IFormatProvider format)
1513                 {
1514                         // FIXME: implement me
1515                         throw new NotImplementedException ();
1516                 }
1517
1518                 [MonoTODO]
1519                 public object ToType (Type conversionType, IFormatProvider provider)
1520                 {
1521                         // FIXME: implement me
1522                         throw new NotImplementedException ();
1523                 }
1524
1525                 [CLSCompliant(false)][MonoTODO]
1526                 public ushort ToUInt16 (IFormatProvider provider)
1527                 {
1528                         // FIXME: implement me
1529                         throw new NotImplementedException ();
1530                 }
1531
1532                 [CLSCompliant(false)][MonoTODO]
1533                 public uint ToUInt32 (IFormatProvider provider)
1534                 {
1535                         // FIXME: implement me
1536                         throw new NotImplementedException ();
1537                 }
1538
1539                 [CLSCompliant(false)][MonoTODO]
1540                 public ulong ToUInt64 (IFormatProvider provider)
1541                 {
1542                         // FIXME: implement me
1543                         throw new NotImplementedException ();
1544                 }
1545
1546                 public string ToUpper ()
1547                 {
1548                         char[] str;
1549                         int i;
1550
1551                         String res = new String (length);
1552                         str = res.c_str;
1553                         for (i = 0; i < this.length; i++)
1554                                 str[i] = Char.ToUpper (this.c_str[i]);
1555
1556                         return res;
1557                 }
1558
1559                 [MonoTODO]
1560                 public string ToUpper (CultureInfo culture)
1561                 {
1562                         // FIXME: implement me
1563                         throw new NotImplementedException ();
1564                 }
1565
1566                 public string Trim ()
1567                 {
1568                         return Trim (null);
1569                 }
1570
1571                 public string Trim (params char[] trimChars)
1572                 {
1573                         int begin, end;
1574                         bool matches;
1575
1576                         matches = true;
1577                         for (begin = 0; matches && begin < this.length; begin++) {
1578                                 if (trimChars != null) {
1579                                         matches = false;
1580                                         foreach (char c in trimChars) {
1581                                                 matches = this.c_str[begin] == c;
1582                                                 if (matches)
1583                                                         break;
1584                                         }
1585                                 } else {
1586                                         matches = is_lwsp (this.c_str[begin]);
1587                                 }
1588                         }
1589
1590                         matches = true;
1591                         for (end = this.length - 1; matches && end > begin; end--) {
1592                                 if (trimChars != null) {
1593                                         matches = false;
1594                                         foreach (char c in trimChars) {
1595                                                 matches = this.c_str[end] == c;
1596                                                 if (matches)
1597                                                         break;
1598                                         }
1599                                 } else {
1600                                         matches = is_lwsp (this.c_str[end]);
1601                                 }
1602                         }
1603
1604                         if (begin >= end)
1605                                 return String.Empty;
1606
1607                         return Substring (begin, end - begin);
1608                 }
1609
1610                 public string TrimEnd (params char[] trimChars)
1611                 {
1612                         bool matches = true;
1613                         int end;
1614
1615                         for (end = this.length; end > 0; end--) {
1616                                 if (trimChars != null) {
1617                                         matches = false;
1618                                         foreach (char c in trimChars) {
1619                                                 matches = this.c_str[end] == c;
1620                                                 if (matches)
1621                                                         break;
1622                                         }
1623                                 } else {
1624                                         matches = is_lwsp (this.c_str[end]);
1625                                 }
1626                         }
1627
1628                         if (end == 0)
1629                                 return String.Empty;
1630
1631                         return Substring (0, end);
1632                 }
1633
1634                 public string TrimStart (params char[] trimChars)
1635                 {
1636                         bool matches = true;
1637                         int begin;
1638
1639                         for (begin = 0; matches && begin < this.length; begin++) {
1640                                 if (trimChars != null) {
1641                                         matches = false;
1642                                         foreach (char c in trimChars) {
1643                                                 matches = this.c_str[begin] == c;
1644                                                 if (matches)
1645                                                         break;
1646                                         }
1647                                 } else {
1648                                         matches = is_lwsp (this.c_str[begin]);
1649                                 }
1650                         }
1651
1652                         if (begin == this.length)
1653                                 return String.Empty;
1654
1655                         return Substring (begin, this.length - begin);
1656                 }
1657
1658                 // Operators
1659                 public static bool operator ==(string a, string b)
1660                 {
1661                         if ((object)a == null) {
1662                                 if ((object)b == null)
1663                                         return true;
1664                                 return false;
1665                         }
1666                         if ((object)b == null)
1667                                 return false;
1668
1669                         if (a.length != b.length)
1670                                 return false;
1671
1672                         int l = a.length;
1673                         for (int i = 0; i < l; i++)
1674                                 if (a.c_str[i] != b.c_str[i])
1675                                         return false;
1676
1677                         return true;
1678                 }
1679
1680                 public static bool operator !=(string a, string b)
1681                 {
1682                         return !(a == b);
1683                 }
1684         }
1685 }