mcs/class/corlib/System/DateTimeOffset.cs

   1 /*
   2  * System.DateTimeOffset
   3  *
   4  * Author(s)
   5  *      Stephane Delcroix <stephane@delcroix.org>
   6  *      Marek Safar (marek.safar@gmail.com)
   7  *
   8  *  Copyright (C) 2007 Novell, Inc (http://www.novell.com)
   9  *
  10  * Permission is hereby granted, free of charge, to any person obtaining
  11  * a copy of this software and associated documentation files (the
  12  * "Software"), to deal in the Software without restriction, including
  13  * without limitation the rights to use, copy, modify, merge, publish,
  14  * distribute, sublicense, and/or sell copies of the Software, and to
  15  * permit persons to whom the Software is furnished to do so, subject to
  16  * the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be
  19  * included in all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28  */
  29
  30
  31 #if NET_2_0 // Introduced by .NET 3.5 for 2.0 mscorlib
  32
  33 using System.Globalization;
  34 using System.Runtime.InteropServices;
  35 using System.Runtime.Serialization;
  36 using System.Text;
  37
  38 namespace System
  39 {
  40         [Serializable]
  41         [StructLayout (LayoutKind.Auto)]
  42         public struct DateTimeOffset : IComparable, IFormattable, ISerializable, IDeserializationCallback, IComparable<DateTimeOffset>, IEquatable<DateTimeOffset>
  43         {
  44                 public static readonly DateTimeOffset MaxValue = new DateTimeOffset (DateTime.MaxValue, TimeSpan.Zero);
  45                 public static readonly DateTimeOffset MinValue = new DateTimeOffset (DateTime.MinValue, TimeSpan.Zero);
  46
  47                 DateTime dt;
  48                 TimeSpan utc_offset;
  49
  50                 public DateTimeOffset (DateTime dateTime)
  51                 {
  52                         dt = dateTime;
  53
  54                         if (dateTime.Kind == DateTimeKind.Utc)
  55                                 utc_offset = TimeSpan.Zero;
  56                         else
  57                                 utc_offset = TimeZone.CurrentTimeZone.GetUtcOffset (dateTime);
  58
  59                         if (UtcDateTime < DateTime.MinValue || UtcDateTime > DateTime.MaxValue)
  60                                 throw new ArgumentOutOfRangeException ("The UTC date and time that results from applying the offset is earlier than MinValue or later than MaxValue.");
  61
  62                 }
  63
  64                 public DateTimeOffset (DateTime dateTime, TimeSpan offset)
  65                 {
  66                         if (dateTime.Kind == DateTimeKind.Utc && offset != TimeSpan.Zero)
  67                                 throw new ArgumentException ("dateTime.Kind equals Utc and offset does not equal zero.");
  68
  69                         if (dateTime.Kind == DateTimeKind.Local && offset != TimeZone.CurrentTimeZone.GetUtcOffset (dateTime))
  70                                 throw new ArgumentException ("dateTime.Kind equals Local and offset does not equal the offset of the system's local time zone.");
  71
  72                         if (offset.Ticks % TimeSpan.TicksPerMinute != 0)
  73                                 throw new ArgumentException ("offset is not specified in whole minutes.");
  74
  75                         if (offset < new TimeSpan (-14, 0 ,0) || offset > new TimeSpan (14, 0, 0))
  76                                 throw new ArgumentOutOfRangeException ("offset is less than -14 hours or greater than 14 hours.");
  77
  78                         dt = dateTime;
  79                         utc_offset = offset;
  80
  81                         if (UtcDateTime < DateTime.MinValue || UtcDateTime > DateTime.MaxValue)
  82                                 throw new ArgumentOutOfRangeException ("The UtcDateTime property is earlier than MinValue or later than MaxValue.");
  83                 }
  84
  85                 public DateTimeOffset (long ticks, TimeSpan offset) : this (new DateTime (ticks), offset)
  86                 {
  87                 }
  88
  89                 public DateTimeOffset (int year, int month, int day, int hour, int minute, int second, TimeSpan offset) :
  90                         this (new DateTime (year, month, day, hour, minute, second), offset)
  91                 {
  92                 }
  93
  94                 public DateTimeOffset (int year, int month, int day, int hour, int minute, int second, int millisecond, TimeSpan offset) :
  95                         this (new DateTime (year, month, day, hour, minute, second, millisecond), offset)
  96                 {
  97                 }
  98
  99                 public DateTimeOffset (int year, int month, int day, int hour, int minute, int second, int millisecond, Calendar calendar, TimeSpan offset) :
 100                         this (new DateTime (year, month, day, hour, minute, second, millisecond, calendar), offset)
 101                 {
 102                 }
 103
 104                 public DateTimeOffset Add (TimeSpan timeSpan)
 105                 {
 106                         return new DateTimeOffset (dt.Add (timeSpan), utc_offset);
 107                 }
 108
 109                 public DateTimeOffset AddDays (double days)
 110                 {
 111                         return new DateTimeOffset (dt.AddDays (days), utc_offset);
 112                 }
 113
 114                 public DateTimeOffset AddHours (double hours)
 115                 {
 116                         return new DateTimeOffset (dt.AddHours (hours), utc_offset);
 117                 }
 118
 119                 public static DateTimeOffset operator + (DateTimeOffset dateTimeTz, TimeSpan timeSpan)
 120                 {
 121                         return dateTimeTz.Add (timeSpan);
 122                 }
 123
 124                 public DateTimeOffset AddMilliseconds (double milliseconds)
 125                 {
 126                         return new DateTimeOffset (dt.AddMilliseconds (milliseconds), utc_offset);
 127                 }
 128
 129                 public DateTimeOffset AddMinutes (double minutes)
 130                 {
 131                         return new DateTimeOffset (dt.AddMinutes (minutes), utc_offset);
 132                 }
 133
 134                 public DateTimeOffset AddMonths (int months)
 135                 {
 136                         return new DateTimeOffset (dt.AddMonths (months), utc_offset);
 137                 }
 138
 139                 public DateTimeOffset AddSeconds (double seconds)
 140                 {
 141                         return new DateTimeOffset (dt.AddSeconds (seconds), utc_offset);
 142                 }
 143
 144                 public DateTimeOffset AddTicks (long ticks)
 145                 {
 146                         return new DateTimeOffset (dt.AddTicks (ticks), utc_offset);
 147                 }
 148
 149                 public DateTimeOffset AddYears (int years)
 150                 {
 151                         return new DateTimeOffset (dt.AddYears (years), utc_offset);
 152                 }
 153
 154                 public static int Compare (DateTimeOffset first, DateTimeOffset second)
 155                 {
 156                         return first.CompareTo (second);
 157                 }
 158
 159                 public int CompareTo (DateTimeOffset other)
 160                 {
 161                         return UtcDateTime.CompareTo (other.UtcDateTime);
 162                 }
 163
 164                 public int CompareTo (object other)
 165                 {
 166                         return CompareTo ((DateTimeOffset) other);
 167                 }
 168
 169                 public static bool operator == (DateTimeOffset left, DateTimeOffset right)
 170                 {
 171                         return left.Equals (right);
 172                 }
 173
 174                 public bool Equals (DateTimeOffset other)
 175                 {
 176                         return UtcDateTime == other.UtcDateTime;
 177                 }
 178
 179                 public override bool Equals (object other)
 180                 {
 181                         return UtcDateTime == ((DateTimeOffset) other).UtcDateTime;
 182                 }
 183
 184                 public static bool Equals (DateTimeOffset first, DateTimeOffset second)
 185                 {
 186                         return first.Equals (second);
 187                 }
 188
 189                 public bool EqualsExact (DateTimeOffset other)
 190                 {
 191                         return dt == other.dt && utc_offset == other.utc_offset;
 192                 }
 193
 194                 public static DateTimeOffset FromFileTime (long fileTime)
 195                 {
 196                         if (fileTime < 0 || fileTime > MaxValue.Ticks)
 197                                 throw new ArgumentOutOfRangeException ("fileTime is less than zero or greater than DateTimeOffset.MaxValue.Ticks.");
 198
 199                         return new DateTimeOffset (DateTime.FromFileTime (fileTime), TimeZone.CurrentTimeZone.GetUtcOffset (DateTime.FromFileTime (fileTime)));
 200
 201                 }
 202
 203                 public override int GetHashCode ()
 204                 {
 205                         return dt.GetHashCode () ^ utc_offset.GetHashCode ();
 206                 }
 207
 208                 void ISerializable.GetObjectData (SerializationInfo info, StreamingContext context)
 209                 {
 210                         if (info == null)
 211                                 throw new ArgumentNullException ("info");
 212
 213                         info.AddValue ("datetime", dt);
 214                         info.AddValue ("offset", utc_offset);
 215                 }
 216
 217                 public static bool operator > (DateTimeOffset left, DateTimeOffset right)
 218                 {
 219                         return left.UtcDateTime > right.UtcDateTime;
 220                 }
 221
 222                 public static bool operator >= (DateTimeOffset left, DateTimeOffset right)
 223                 {
 224                         return left.UtcDateTime >= right.UtcDateTime;
 225                 }
 226
 227                 public static implicit operator DateTimeOffset (DateTime dateTime)
 228                 {
 229                         return new DateTimeOffset (dateTime);
 230                 }
 231
 232                 public static bool operator != (DateTimeOffset left, DateTimeOffset right)
 233                 {
 234                         return left.UtcDateTime != right.UtcDateTime;
 235                 }
 236
 237                 public static bool operator < (DateTimeOffset left, DateTimeOffset right)
 238                 {
 239                         return left.UtcDateTime < right.UtcDateTime;
 240                 }
 241
 242                 public static bool operator <= (DateTimeOffset left, DateTimeOffset right)
 243                 {
 244                         return left.UtcDateTime <= right.UtcDateTime;
 245                 }
 246
 247                 [MonoTODO]
 248                 void IDeserializationCallback.OnDeserialization (object sender)
 249                 {
 250                 }
 251
 252                 public static DateTimeOffset Parse (string input)
 253                 {
 254                         return Parse (input, null);
 255                 }
 256
 257                 public static DateTimeOffset Parse (string input, IFormatProvider formatProvider)
 258                 {
 259                         return Parse (input, formatProvider, DateTimeStyles.AllowWhiteSpaces);
 260                 }
 261
 262                 [MonoTODO]
 263                 public static DateTimeOffset Parse (string input, IFormatProvider formatProvider, DateTimeStyles styles)
 264                 {
 265                         if (input == null)
 266                                 throw new ArgumentNullException ("input");
 267
 268                         throw new NotImplementedException ();
 269                 }
 270
 271                 public static DateTimeOffset ParseExact (string input, string format, IFormatProvider formatProvider)
 272                 {
 273                         return ParseExact (input, format, formatProvider, DateTimeStyles.AssumeLocal);
 274                 }
 275
 276                 public static DateTimeOffset ParseExact (string input, string format, IFormatProvider formatProvider, DateTimeStyles styles)
 277                 {
 278                         if (format == null)
 279                                 throw new ArgumentNullException ("format");
 280
 281                         if (format == String.Empty)
 282                                 throw new FormatException ("format is an empty string");
 283
 284                         return ParseExact (input, new string [] {format}, formatProvider, styles);
 285                 }
 286
 287                 public static DateTimeOffset ParseExact (string input, string[] formats, IFormatProvider formatProvider, DateTimeStyles styles)
 288                 {
 289                         if (input == null)
 290                                 throw new ArgumentNullException ("input");
 291
 292                         if (input == String.Empty)
 293                                 throw new FormatException ("input is an empty string");
 294
 295                         if (formats == null)
 296                                 throw new ArgumentNullException ("formats");
 297
 298                         if (formats.Length == 0)
 299                                 throw new FormatException ("Invalid format specifier");
 300
 301                         if ((styles & DateTimeStyles.AssumeLocal) != 0 && (styles & DateTimeStyles.AssumeUniversal) != 0)
 302                                 throw new ArgumentException ("styles parameter contains incompatible flags");
 303
 304                         DateTimeOffset result;
 305                         if (!ParseExact (input, formats, DateTimeFormatInfo.GetInstance (formatProvider), styles, out result))
 306                                 throw new FormatException ();
 307
 308                         return result;
 309                 }
 310
 311                 private static bool ParseExact (string input, string [] formats,
 312                                 DateTimeFormatInfo dfi, DateTimeStyles styles, out DateTimeOffset ret)
 313                 {
 314                         foreach (string format in formats)
 315                         {
 316                                 if (format == null || format == String.Empty)
 317                                         throw new FormatException ("Invlid Format Sting");
 318
 319                                 DateTimeOffset result;
 320                                 if (DoParse (input, format, false, out result, dfi, styles)) {
 321                                         ret = result;
 322                                         return true;
 323                                 }
 324                         }
 325                         ret = DateTimeOffset.MinValue;
 326                         return false;
 327                 }
 328
 329                 private static bool DoParse (string input,
 330                                 string format,
 331                                 bool exact,
 332                                 out DateTimeOffset result,
 333                                 DateTimeFormatInfo dfi,
 334                                 DateTimeStyles styles)
 335                 {
 336                         if ((styles & DateTimeStyles.AllowLeadingWhite) != 0) {
 337                                 format = format.TrimStart (null);
 338                                 input = input.TrimStart (null);
 339                         }
 340
 341                         if ((styles & DateTimeStyles.AllowTrailingWhite) != 0) {
 342                                 format = format.TrimEnd (null);
 343                                 input = input.TrimEnd (null);
 344                         }
 345
 346                         bool allow_white_spaces = false;
 347                         if ((styles & DateTimeStyles.AllowInnerWhite) != 0)
 348                                 allow_white_spaces = true;
 349
 350                         bool useutc = false, use_invariants = false;
 351                         if (format.Length == 1)
 352                                 format = DateTimeUtils.GetStandardPattern (format[0], dfi, out useutc, out use_invariants, true);
 353
 354                         int year = -1;
 355                         int month = -1;
 356                         int day = -1;
 357                         int partial_hour = -1; // for 'hh tt' formats
 358                         int hour = -1;
 359                         int minute = -1;
 360                         int second = -1;
 361                         double fraction = -1;
 362                         int temp_int = -1;
 363                         TimeSpan offset = TimeSpan.MinValue;
 364
 365                         result = DateTimeOffset.MinValue;
 366
 367                         int fi = 0; //format iterator
 368                         int ii = 0; //input iterator
 369                         while (fi < format.Length) {
 370                                 int tokLen;
 371                                 char ch = format [fi];
 372
 373                                 switch (ch) {
 374                                 case 'd':
 375                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 376                                         if (day != -1 || tokLen > 4)
 377                                                 return false;
 378
 379                                         if (tokLen <= 2)
 380                                                 ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out day);
 381                                         else
 382                                                 ii += ParseEnum (input, ii, tokLen == 3 ? dfi.AbbreviatedDayNames : dfi.DayNames, allow_white_spaces, out temp_int);
 383                                         break;
 384                                 case 'f':
 385                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 386                                         ii += ParseNumber (input, ii, tokLen, true, allow_white_spaces, out temp_int);
 387                                         if (fraction >= 0 || tokLen > 7 || temp_int == -1)
 388                                                 return false;
 389                                         fraction = (double)temp_int / Math.Pow (10, tokLen);
 390                                         break;
 391                                 case 'F':
 392                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 393                                         int digits;
 394                                         int read = ParseNumber (input, ii, tokLen, true, allow_white_spaces, out temp_int, out digits);
 395                                         if (temp_int == -1)
 396                                                 ii += ParseNumber (input, ii, digits, true, allow_white_spaces, out temp_int);
 397                                         else
 398                                                 ii += read;
 399                                         if (fraction >= 0 || tokLen > 7 || temp_int == -1)
 400                                                 return false;
 401                                         fraction = (double)temp_int / Math.Pow (10, digits);
 402                                         break;
 403                                 case 'h':
 404                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 405                                         if (hour != -1 || tokLen > 2)
 406                                                 return false;
 407
 408                                         ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out temp_int);
 409                                         if (temp_int == -1)
 410                                                 return false;
 411
 412                                         if (partial_hour == -1)
 413                                                 partial_hour = temp_int;
 414                                         else
 415                                                 hour = partial_hour + temp_int;
 416                                         break;
 417                                 case 'H':
 418                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 419                                         if (hour != -1 || tokLen > 2)
 420                                                 return false;
 421
 422                                         ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out hour);
 423                                         break;
 424                                 case 'm':
 425                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 426                                         if (minute != -1 || tokLen > 2)
 427                                                 return false;
 428
 429                                         ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out minute);
 430                                         break;
 431                                 case 'M':
 432                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 433                                         if (month != -1 || tokLen > 4)
 434                                                 return false;
 435
 436                                         if (tokLen <= 2)
 437                                                 ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out month);
 438                                         else {
 439                                                 ii += ParseEnum (input, ii, tokLen == 3 ? dfi.AbbreviatedMonthNames : dfi.MonthNames, allow_white_spaces, out month);
 440                                                 month += 1;
 441                                         }
 442
 443                                         break;
 444                                 case 's':
 445                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 446                                         if (second != -1 || tokLen > 2)
 447                                                 return false;
 448                                         ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out second);
 449                                         break;
 450                                 case 't':
 451                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 452                                         if (hour != -1 || tokLen > 2)
 453                                                 return false;
 454
 455                                         ii += ParseEnum (input, ii,
 456                                                          tokLen == 1 ? new string[] {new string (dfi.AMDesignator[0], 1), new string (dfi.PMDesignator[0], 0)}
 457                                                                      : new string[] {dfi.AMDesignator, dfi.PMDesignator},
 458                                                          allow_white_spaces, out temp_int);
 459                                         if (temp_int == -1)
 460                                                 return false;
 461
 462                                         if (partial_hour == -1)
 463                                                 partial_hour = temp_int * 12;
 464                                         else
 465                                                 hour = partial_hour + temp_int * 12;
 466                                         break;
 467                                 case 'y':
 468                                         if (year != -1)
 469                                                 return false;
 470
 471                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 472                                         if (tokLen <= 2) {
 473                                                 ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out year);
 474                                                 if (year != -1)
 475                                                         year += DateTime.Now.Year - DateTime.Now.Year % 100;
 476                                         } else if (tokLen <= 4) { // yyy and yyyy accept up to 5 digits with leading 0
 477                                                 int digit_parsed;
 478                                                 ii += ParseNumber (input, ii, 5, false, allow_white_spaces, out year, out digit_parsed);
 479                                                 if (digit_parsed < tokLen || (digit_parsed > tokLen && (year / Math.Pow (10, digit_parsed - 1) < 1)))
 480                                                         return false;
 481                                         } else
 482                                                 ii += ParseNumber (input, ii, tokLen, true, allow_white_spaces, out year);
 483                                         break;
 484                                 case 'z':
 485                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 486                                         if (offset != TimeSpan.MinValue || tokLen > 3)
 487                                                 return false;
 488
 489                                         int off_h, off_m = 0, sign;
 490                                         temp_int = 0;
 491                                         ii += ParseEnum (input, ii, new string [] {"-", "+"}, allow_white_spaces, out sign);
 492                                         ii += ParseNumber (input, ii, 2, tokLen != 1, false, out off_h);
 493                                         if (tokLen == 3) {
 494                                                 ii += ParseEnum (input, ii, new string [] {dfi.TimeSeparator}, false, out temp_int);
 495                                                 ii += ParseNumber (input, ii, 2, true, false, out off_m);
 496                                         }
 497                                         if (off_h == -1 || off_m == -1 || sign == -1 || temp_int == -1)
 498                                                 return false;
 499
 500                                         if (sign == 0)
 501                                                 sign = -1;
 502                                         offset = new TimeSpan (sign * off_h, sign * off_m, 0);
 503                                         break;
 504                                 case ':':
 505                                         tokLen = 1;
 506                                         ii += ParseEnum (input, ii, new string [] {dfi.TimeSeparator}, false, out temp_int);
 507                                         if (temp_int == -1)
 508                                                 return false;
 509                                         break;
 510                                 case '/':
 511                                         tokLen = 1;
 512                                         ii += ParseEnum (input, ii, new string [] {dfi.DateSeparator}, false, out temp_int);
 513                                         if (temp_int == -1)
 514                                                 return false;
 515                                         break;
 516                                 case '%':
 517                                         tokLen = 1;
 518                                         if (fi != 0)
 519                                                 return false;
 520                                         break;
 521                                 case ' ':
 522                                         tokLen = 1;
 523                                         ii += ParseChar (input, ii, ' ', false, out temp_int);
 524                                         if (temp_int == -1)
 525                                                 return false;
 526                                         break;
 527                                 case '\\':
 528                                         tokLen = 2;
 529                                         ii += ParseChar (input, ii, format [fi + 1], allow_white_spaces, out temp_int);
 530                                         if (temp_int == -1)
 531                                                 return false;
 532                                         break;
 533                                 default:
 534                                         //Console.WriteLine ("un-parsed character: {0}", ch);
 535                                         tokLen = 1;
 536                                         ii += ParseChar (input, ii, format [fi], allow_white_spaces, out temp_int);
 537                                         if (temp_int == -1)
 538                                                 return false;
 539                                         break;
 540                                 }
 541                                 fi += tokLen;
 542                         }
 543
 544                         //Console.WriteLine ("{0}-{1}-{2} {3}:{4} {5}", year, month, day, hour, minute, offset);
 545                         if (offset == TimeSpan.MinValue && (styles & DateTimeStyles.AssumeLocal) != 0)
 546                                 offset = TimeZone.CurrentTimeZone.GetUtcOffset (DateTime.Now);
 547
 548                         if (offset == TimeSpan.MinValue && (styles & DateTimeStyles.AssumeUniversal) != 0)
 549                                 offset = TimeSpan.Zero;
 550
 551                         if (hour < 0)           hour = 0;
 552                         if (minute < 0)         minute = 0;
 553                         if (second < 0)         second = 0;
 554                         if (fraction < 0)       fraction = 0;
 555                         if (year > 0 && month > 0 && day > 0) {
 556                                 result = new DateTimeOffset (year, month, day, hour, minute, second, (int) (1000 * fraction), offset);
 557                                 if ((styles & DateTimeStyles.AdjustToUniversal) != 0)
 558                                         result = result.ToUniversalTime ();
 559                                 return true;
 560                         }
 561
 562                         return false;
 563                 }
 564
 565                 private static int ParseNumber (string input, int pos, int digits, bool leading_zero, bool allow_leading_white, out int result)
 566                 {
 567                         int digit_parsed;
 568                         return ParseNumber (input, pos, digits, leading_zero, allow_leading_white, out result, out digit_parsed);
 569                 }
 570
 571                 private static int ParseNumber (string input, int pos, int digits, bool leading_zero, bool allow_leading_white, out int result, out int digit_parsed)
 572                 {
 573                         int char_parsed = 0;
 574                         digit_parsed = 0;
 575                         result = 0;
 576                         for (; allow_leading_white && pos < input.Length && input[pos] == ' '; pos++)
 577                                 char_parsed++;
 578
 579                         for (; pos < input.Length && Char.IsDigit (input[pos]) && digits > 0; pos ++, char_parsed++, digit_parsed++, digits --)
 580                                 result = 10 * result + (byte) (input[pos] - '0');
 581
 582                         if (leading_zero && digits > 0)
 583                                 result = -1;
 584
 585                         if (digit_parsed == 0)
 586                                 result = -1;
 587
 588                         return char_parsed;
 589                 }
 590
 591                 private static int ParseEnum (string input, int pos, string [] enums, bool allow_leading_white, out int result)
 592                 {
 593                         int char_parsed = 0;
 594                         result = -1;
 595                         for (; allow_leading_white && pos < input.Length && input[pos] == ' '; pos++)
 596                                 char_parsed ++;
 597
 598                         for (int i = 0; i < enums.Length; i++)
 599                                 if (input.Substring(pos).StartsWith (enums [i])) {
 600                                         result = i;
 601                                         break;
 602                                 }
 603
 604                         if (result >= 0)
 605                                 char_parsed += enums[result].Length;
 606
 607                         return char_parsed;
 608                 }
 609
 610                 private static int ParseChar (string input, int pos, char c, bool allow_leading_white, out int result)
 611                 {
 612                         int char_parsed = 0;
 613                         result = -1;
 614                         for (; allow_leading_white && pos < input.Length && input[pos] == ' '; pos++, char_parsed++)
 615                                 ;
 616
 617                         if (pos < input.Length && input[pos] == c){
 618                                 result = (int) c;
 619                                 char_parsed ++;
 620                         }
 621
 622                         return char_parsed;
 623                 }
 624
 625                 public TimeSpan Subtract (DateTimeOffset other)
 626                 {
 627                         return UtcDateTime - other.UtcDateTime;
 628                 }
 629
 630                 public DateTimeOffset Subtract (TimeSpan timeSpan)
 631                 {
 632                         return Add (-timeSpan);
 633                 }
 634
 635                 public static TimeSpan operator - (DateTimeOffset left, DateTimeOffset right)
 636                 {
 637                         return left.Subtract (right);
 638                 }
 639
 640                 public static DateTimeOffset operator - (DateTimeOffset dateTimeTz, TimeSpan timeSpan)
 641                 {
 642                         return dateTimeTz.Subtract (timeSpan);
 643                 }
 644
 645                 public long ToFileTime ()
 646                 {
 647                         return UtcDateTime.ToFileTime ();
 648                 }
 649
 650                 public DateTimeOffset ToLocalTime ()
 651                 {
 652                         return new DateTimeOffset (UtcDateTime.ToLocalTime (), TimeZone.CurrentTimeZone.GetUtcOffset (UtcDateTime.ToLocalTime ()));
 653                 }
 654
 655                 public DateTimeOffset ToOffset (TimeSpan offset)
 656                 {
 657                         return new DateTimeOffset (dt - utc_offset + offset, offset);
 658                 }
 659
 660                 public override string ToString ()
 661                 {
 662                         return ToString (null, null);
 663                 }
 664
 665                 public string ToString (IFormatProvider formatProvider)
 666                 {
 667                         return ToString (null, formatProvider);
 668                 }
 669
 670                 public string ToString (string format)
 671                 {
 672                         return ToString (format, null);
 673                 }
 674
 675                 public string ToString (string format, IFormatProvider formatProvider)
 676                 {
 677                         DateTimeFormatInfo dfi = DateTimeFormatInfo.GetInstance(formatProvider);
 678
 679                         if (format == null || format == String.Empty)
 680                                 format = dfi.ShortDatePattern + " " + dfi.LongTimePattern + " zzz";
 681
 682                         bool to_utc = false, use_invariant = false;
 683                         if (format.Length == 1) {
 684                                 char fchar = format [0];
 685                                 try {
 686                                         format = DateTimeUtils.GetStandardPattern (fchar, dfi, out to_utc, out use_invariant, true);
 687                                 } catch {
 688                                         format = null;
 689                                 }
 690
 691                                 if (format == null)
 692                                         throw new FormatException ("format is not one of the format specifier characters defined for DateTimeFormatInfo");
 693                         }
 694                         return to_utc ? DateTimeUtils.ToString (UtcDateTime, TimeSpan.Zero, format, dfi) : DateTimeUtils.ToString (DateTime, Offset, format, dfi);
 695                 }
 696
 697                 public DateTimeOffset ToUniversalTime ()
 698                 {
 699                         return new DateTimeOffset (UtcDateTime, TimeSpan.Zero);
 700                 }
 701
 702                 public static bool TryParse (string input, out DateTimeOffset result)
 703                 {
 704                         try {
 705                                 result = Parse (input);
 706                                 return true;
 707                         } catch {
 708                                 result = MinValue;
 709                                 return false;
 710                         }
 711                 }
 712
 713                 public static bool TryParse (string input, IFormatProvider formatProvider, DateTimeStyles styles, out DateTimeOffset result)
 714                 {
 715                         try {
 716                                 result = Parse (input, formatProvider, styles);
 717                                 return true;
 718                         } catch {
 719                                 result = MinValue;
 720                                 return false;
 721                         }
 722                 }
 723
 724                 public static bool TryParseExact (string input, string format, IFormatProvider formatProvider, DateTimeStyles styles, out DateTimeOffset result)
 725                 {
 726                         try {
 727                                 result = ParseExact (input, format, formatProvider, styles);
 728                                 return true;
 729                         } catch {
 730                                 result = MinValue;
 731                                 return false;
 732                         }
 733                 }
 734
 735                 public static bool TryParseExact (string input, string[] formats, IFormatProvider formatProvider, DateTimeStyles styles, out DateTimeOffset result)
 736                 {
 737                         try {
 738                                 result = ParseExact (input, formats, formatProvider, styles);
 739                                 return true;
 740                         } catch {
 741                                 result = MinValue;
 742                                 return false;
 743                         }
 744                 }
 745
 746                 public DateTime Date {
 747                         get { return DateTime.SpecifyKind (dt.Date, DateTimeKind.Unspecified); }
 748                 }
 749
 750                 public DateTime DateTime {
 751                         get { return DateTime.SpecifyKind (dt, DateTimeKind.Unspecified); }
 752                 }
 753
 754                 public int Day {
 755                         get { return dt.Day; }
 756                 }
 757
 758                 public DayOfWeek DayOfWeek {
 759                         get { return dt.DayOfWeek; }
 760                 }
 761
 762                 public int DayOfYear {
 763                         get { return dt.DayOfYear; }
 764                 }
 765
 766                 public int Hour {
 767                         get { return dt.Hour; }
 768                 }
 769
 770                 public DateTime LocalDateTime {
 771                         get { return UtcDateTime.ToLocalTime (); }
 772                 }
 773
 774                 public int Millisecond {
 775                         get { return dt.Millisecond; }
 776                 }
 777
 778                 public int Minute {
 779                         get { return dt.Minute; }
 780                 }
 781
 782                 public int Month {
 783                         get { return dt.Month; }
 784                 }
 785
 786                 public static DateTimeOffset Now {
 787                         get { return new DateTimeOffset (DateTime.Now);}
 788                 }
 789
 790                 public TimeSpan Offset {
 791                         get { return utc_offset; }
 792                 }
 793
 794                 public int Second {
 795                         get { return dt.Second; }
 796                 }
 797
 798                 public long Ticks {
 799                         get { return dt.Ticks; }
 800                 }
 801
 802                 public TimeSpan TimeOfDay {
 803                         get { return dt.TimeOfDay; }
 804                 }
 805
 806                 public DateTime UtcDateTime {
 807                         get { return DateTime.SpecifyKind (dt - utc_offset, DateTimeKind.Utc); }
 808                 }
 809
 810                 public static DateTimeOffset UtcNow {
 811                         get { return new DateTimeOffset (DateTime.UtcNow); }
 812                 }
 813
 814                 public long UtcTicks {
 815                         get { return UtcDateTime.Ticks; }
 816                 }
 817
 818                 public int Year {
 819                         get { return dt.Year; }
 820                 }
 821         }
 822 }
 823 #endif