mcs/class/corlib/System/DateTimeOffset.cs

   1 /*
   2  * System.DateTimeOffset.cs
   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                 int IComparable.CompareTo (object obj)
 165                 {
 166                         return CompareTo ((DateTimeOffset) obj);
 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 obj)
 180                 {
 181                         if (obj is DateTimeOffset)
 182                                 return UtcDateTime == ((DateTimeOffset) obj).UtcDateTime;
 183                         return false;
 184                 }
 185
 186                 public static bool Equals (DateTimeOffset first, DateTimeOffset second)
 187                 {
 188                         return first.Equals (second);
 189                 }
 190
 191                 public bool EqualsExact (DateTimeOffset other)
 192                 {
 193                         return dt == other.dt && utc_offset == other.utc_offset;
 194                 }
 195
 196                 public static DateTimeOffset FromFileTime (long fileTime)
 197                 {
 198                         if (fileTime < 0 || fileTime > MaxValue.Ticks)
 199                                 throw new ArgumentOutOfRangeException ("fileTime is less than zero or greater than DateTimeOffset.MaxValue.Ticks.");
 200
 201                         return new DateTimeOffset (DateTime.FromFileTime (fileTime), TimeZone.CurrentTimeZone.GetUtcOffset (DateTime.FromFileTime (fileTime)));
 202
 203                 }
 204
 205                 public override int GetHashCode ()
 206                 {
 207                         return dt.GetHashCode () ^ utc_offset.GetHashCode ();
 208                 }
 209
 210                 [System.Security.Permissions.SecurityPermission (System.Security.Permissions.SecurityAction.LinkDemand, SerializationFormatter = true)]
 211                 void ISerializable.GetObjectData (SerializationInfo info, StreamingContext context)
 212                 {
 213                         if (info == null)
 214                                 throw new ArgumentNullException ("info");
 215                         // An example SOAP serialization on MSFT is the following, so field
 216                         // names "DateTime" and "OffsetMinutes":
 217                         //    <SOAP-ENV:Envelope ...>
 218                         //    <SOAP-ENV:Body>
 219                         //    <a1:DateTimeOffset id="ref-1" xmlns:a1="http://schemas.microsoft.com/clr/ns/System">
 220                         //    <DateTime xsi:type="xsd:dateTime">2007-01-02T12:30:50.0000000+00:00</DateTime>
 221                         //    <OffsetMinutes>0</OffsetMinutes>
 222                         //    </a1:DateTimeOffset>
 223                         //    </SOAP-ENV:Body>
 224                         //    </SOAP-ENV:Envelope>
 225                         DateTime dt0 = new DateTime (dt.Ticks).Subtract (utc_offset);
 226                         info.AddValue ("DateTime", dt0);
 227                         // MSFT BinaryFormatter output contains primitive code 6, i.e. Int16.
 228                         info.AddValue ("OffsetMinutes", (Int16)utc_offset.TotalMinutes);
 229                 }
 230
 231                 [System.Security.Permissions.SecurityPermission (System.Security.Permissions.SecurityAction.LinkDemand, SerializationFormatter = true)]
 232                 private DateTimeOffset(SerializationInfo info, StreamingContext context)
 233                 {
 234                         DateTime dt0 = (DateTime)info.GetValue ("DateTime", typeof(DateTime));
 235                         Int16 totalMinutes = info.GetInt16 ("OffsetMinutes");
 236                         utc_offset = TimeSpan.FromMinutes(totalMinutes);
 237                         dt = dt0.Add(utc_offset);
 238                 }
 239
 240                 public static bool operator > (DateTimeOffset left, DateTimeOffset right)
 241                 {
 242                         return left.UtcDateTime > right.UtcDateTime;
 243                 }
 244
 245                 public static bool operator >= (DateTimeOffset left, DateTimeOffset right)
 246                 {
 247                         return left.UtcDateTime >= right.UtcDateTime;
 248                 }
 249
 250                 public static implicit operator DateTimeOffset (DateTime dateTime)
 251                 {
 252                         return new DateTimeOffset (dateTime);
 253                 }
 254
 255                 public static bool operator != (DateTimeOffset left, DateTimeOffset right)
 256                 {
 257                         return left.UtcDateTime != right.UtcDateTime;
 258                 }
 259
 260                 public static bool operator < (DateTimeOffset left, DateTimeOffset right)
 261                 {
 262                         return left.UtcDateTime < right.UtcDateTime;
 263                 }
 264
 265                 public static bool operator <= (DateTimeOffset left, DateTimeOffset right)
 266                 {
 267                         return left.UtcDateTime <= right.UtcDateTime;
 268                 }
 269
 270                 [MonoTODO]
 271                 void IDeserializationCallback.OnDeserialization (object sender)
 272                 {
 273                 }
 274
 275                 public static DateTimeOffset Parse (string input)
 276                 {
 277                         return Parse (input, null);
 278                 }
 279
 280                 public static DateTimeOffset Parse (string input, IFormatProvider formatProvider)
 281                 {
 282                         return Parse (input, formatProvider, DateTimeStyles.AllowWhiteSpaces);
 283                 }
 284
 285                 [MonoTODO]
 286                 public static DateTimeOffset Parse (string input, IFormatProvider formatProvider, DateTimeStyles styles)
 287                 {
 288                         if (input == null)
 289                                 throw new ArgumentNullException ("input");
 290
 291                         throw new NotImplementedException ();
 292                 }
 293
 294                 public static DateTimeOffset ParseExact (string input, string format, IFormatProvider formatProvider)
 295                 {
 296                         return ParseExact (input, format, formatProvider, DateTimeStyles.AssumeLocal);
 297                 }
 298
 299                 public static DateTimeOffset ParseExact (string input, string format, IFormatProvider formatProvider, DateTimeStyles styles)
 300                 {
 301                         if (format == null)
 302                                 throw new ArgumentNullException ("format");
 303
 304                         if (format == String.Empty)
 305                                 throw new FormatException ("format is an empty string");
 306
 307                         return ParseExact (input, new string [] {format}, formatProvider, styles);
 308                 }
 309
 310                 public static DateTimeOffset ParseExact (string input, string[] formats, IFormatProvider formatProvider, DateTimeStyles styles)
 311                 {
 312                         if (input == null)
 313                                 throw new ArgumentNullException ("input");
 314
 315                         if (input == String.Empty)
 316                                 throw new FormatException ("input is an empty string");
 317
 318                         if (formats == null)
 319                                 throw new ArgumentNullException ("formats");
 320
 321                         if (formats.Length == 0)
 322                                 throw new FormatException ("Invalid format specifier");
 323
 324                         if ((styles & DateTimeStyles.AssumeLocal) != 0 && (styles & DateTimeStyles.AssumeUniversal) != 0)
 325                                 throw new ArgumentException ("styles parameter contains incompatible flags");
 326
 327                         DateTimeOffset result;
 328                         if (!ParseExact (input, formats, DateTimeFormatInfo.GetInstance (formatProvider), styles, out result))
 329                                 throw new FormatException ();
 330
 331                         return result;
 332                 }
 333
 334                 private static bool ParseExact (string input, string [] formats,
 335                                 DateTimeFormatInfo dfi, DateTimeStyles styles, out DateTimeOffset ret)
 336                 {
 337                         foreach (string format in formats)
 338                         {
 339                                 if (format == null || format == String.Empty)
 340                                         throw new FormatException ("Invlid Format Sting");
 341
 342                                 DateTimeOffset result;
 343                                 if (DoParse (input, format, false, out result, dfi, styles)) {
 344                                         ret = result;
 345                                         return true;
 346                                 }
 347                         }
 348                         ret = DateTimeOffset.MinValue;
 349                         return false;
 350                 }
 351
 352                 private static bool DoParse (string input,
 353                                 string format,
 354                                 bool exact,
 355                                 out DateTimeOffset result,
 356                                 DateTimeFormatInfo dfi,
 357                                 DateTimeStyles styles)
 358                 {
 359                         if ((styles & DateTimeStyles.AllowLeadingWhite) != 0) {
 360                                 format = format.TrimStart (null);
 361                                 input = input.TrimStart (null);
 362                         }
 363
 364                         if ((styles & DateTimeStyles.AllowTrailingWhite) != 0) {
 365                                 format = format.TrimEnd (null);
 366                                 input = input.TrimEnd (null);
 367                         }
 368
 369                         bool allow_white_spaces = false;
 370                         if ((styles & DateTimeStyles.AllowInnerWhite) != 0)
 371                                 allow_white_spaces = true;
 372
 373                         bool useutc = false, use_invariants = false;
 374                         if (format.Length == 1)
 375                                 format = DateTimeUtils.GetStandardPattern (format[0], dfi, out useutc, out use_invariants, true);
 376
 377                         int year = -1;
 378                         int month = -1;
 379                         int day = -1;
 380                         int partial_hour = -1; // for 'hh tt' formats
 381                         int hour = -1;
 382                         int minute = -1;
 383                         int second = -1;
 384                         double fraction = -1;
 385                         int temp_int = -1;
 386                         TimeSpan offset = TimeSpan.MinValue;
 387
 388                         result = DateTimeOffset.MinValue;
 389
 390                         int fi = 0; //format iterator
 391                         int ii = 0; //input iterator
 392                         while (fi < format.Length) {
 393                                 int tokLen;
 394                                 char ch = format [fi];
 395
 396                                 switch (ch) {
 397                                 case 'd':
 398                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 399                                         if (day != -1 || tokLen > 4)
 400                                                 return false;
 401
 402                                         if (tokLen <= 2)
 403                                                 ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out day);
 404                                         else
 405                                                 ii += ParseEnum (input, ii, tokLen == 3 ? dfi.AbbreviatedDayNames : dfi.DayNames, allow_white_spaces, out temp_int);
 406                                         break;
 407                                 case 'f':
 408                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 409                                         ii += ParseNumber (input, ii, tokLen, true, allow_white_spaces, out temp_int);
 410                                         if (fraction >= 0 || tokLen > 7 || temp_int == -1)
 411                                                 return false;
 412                                         fraction = (double)temp_int / Math.Pow (10, tokLen);
 413                                         break;
 414                                 case 'F':
 415                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 416                                         int digits;
 417                                         int read = ParseNumber (input, ii, tokLen, true, allow_white_spaces, out temp_int, out digits);
 418                                         if (temp_int == -1)
 419                                                 ii += ParseNumber (input, ii, digits, true, allow_white_spaces, out temp_int);
 420                                         else
 421                                                 ii += read;
 422                                         if (fraction >= 0 || tokLen > 7 || temp_int == -1)
 423                                                 return false;
 424                                         fraction = (double)temp_int / Math.Pow (10, digits);
 425                                         break;
 426                                 case 'h':
 427                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 428                                         if (hour != -1 || tokLen > 2)
 429                                                 return false;
 430
 431                                         ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out temp_int);
 432                                         if (temp_int == -1)
 433                                                 return false;
 434
 435                                         if (partial_hour == -1)
 436                                                 partial_hour = temp_int;
 437                                         else
 438                                                 hour = partial_hour + temp_int;
 439                                         break;
 440                                 case 'H':
 441                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 442                                         if (hour != -1 || tokLen > 2)
 443                                                 return false;
 444
 445                                         ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out hour);
 446                                         break;
 447                                 case 'm':
 448                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 449                                         if (minute != -1 || tokLen > 2)
 450                                                 return false;
 451
 452                                         ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out minute);
 453                                         break;
 454                                 case 'M':
 455                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 456                                         if (month != -1 || tokLen > 4)
 457                                                 return false;
 458
 459                                         if (tokLen <= 2)
 460                                                 ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out month);
 461                                         else {
 462                                                 ii += ParseEnum (input, ii, tokLen == 3 ? dfi.AbbreviatedMonthNames : dfi.MonthNames, allow_white_spaces, out month);
 463                                                 month += 1;
 464                                         }
 465
 466                                         break;
 467                                 case 's':
 468                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 469                                         if (second != -1 || tokLen > 2)
 470                                                 return false;
 471                                         ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out second);
 472                                         break;
 473                                 case 't':
 474                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 475                                         if (hour != -1 || tokLen > 2)
 476                                                 return false;
 477
 478                                         ii += ParseEnum (input, ii,
 479                                                          tokLen == 1 ? new string[] {new string (dfi.AMDesignator[0], 1), new string (dfi.PMDesignator[0], 0)}
 480                                                                      : new string[] {dfi.AMDesignator, dfi.PMDesignator},
 481                                                          allow_white_spaces, out temp_int);
 482                                         if (temp_int == -1)
 483                                                 return false;
 484
 485                                         if (partial_hour == -1)
 486                                                 partial_hour = temp_int * 12;
 487                                         else
 488                                                 hour = partial_hour + temp_int * 12;
 489                                         break;
 490                                 case 'y':
 491                                         if (year != -1)
 492                                                 return false;
 493
 494                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 495                                         if (tokLen <= 2) {
 496                                                 ii += ParseNumber (input, ii, 2, tokLen == 2, allow_white_spaces, out year);
 497                                                 if (year != -1)
 498                                                         year += DateTime.Now.Year - DateTime.Now.Year % 100;
 499                                         } else if (tokLen <= 4) { // yyy and yyyy accept up to 5 digits with leading 0
 500                                                 int digit_parsed;
 501                                                 ii += ParseNumber (input, ii, 5, false, allow_white_spaces, out year, out digit_parsed);
 502                                                 if (digit_parsed < tokLen || (digit_parsed > tokLen && (year / Math.Pow (10, digit_parsed - 1) < 1)))
 503                                                         return false;
 504                                         } else
 505                                                 ii += ParseNumber (input, ii, tokLen, true, allow_white_spaces, out year);
 506                                         break;
 507                                 case 'z':
 508                                         tokLen = DateTimeUtils.CountRepeat (format, fi, ch);
 509                                         if (offset != TimeSpan.MinValue || tokLen > 3)
 510                                                 return false;
 511
 512                                         int off_h, off_m = 0, sign;
 513                                         temp_int = 0;
 514                                         ii += ParseEnum (input, ii, new string [] {"-", "+"}, allow_white_spaces, out sign);
 515                                         ii += ParseNumber (input, ii, 2, tokLen != 1, false, out off_h);
 516                                         if (tokLen == 3) {
 517                                                 ii += ParseEnum (input, ii, new string [] {dfi.TimeSeparator}, false, out temp_int);
 518                                                 ii += ParseNumber (input, ii, 2, true, false, out off_m);
 519                                         }
 520                                         if (off_h == -1 || off_m == -1 || sign == -1 || temp_int == -1)
 521                                                 return false;
 522
 523                                         if (sign == 0)
 524                                                 sign = -1;
 525                                         offset = new TimeSpan (sign * off_h, sign * off_m, 0);
 526                                         break;
 527                                 case ':':
 528                                         tokLen = 1;
 529                                         ii += ParseEnum (input, ii, new string [] {dfi.TimeSeparator}, false, out temp_int);
 530                                         if (temp_int == -1)
 531                                                 return false;
 532                                         break;
 533                                 case '/':
 534                                         tokLen = 1;
 535                                         ii += ParseEnum (input, ii, new string [] {dfi.DateSeparator}, false, out temp_int);
 536                                         if (temp_int == -1)
 537                                                 return false;
 538                                         break;
 539                                 case '%':
 540                                         tokLen = 1;
 541                                         if (fi != 0)
 542                                                 return false;
 543                                         break;
 544                                 case ' ':
 545                                         tokLen = 1;
 546                                         ii += ParseChar (input, ii, ' ', false, out temp_int);
 547                                         if (temp_int == -1)
 548                                                 return false;
 549                                         break;
 550                                 case '\\':
 551                                         tokLen = 2;
 552                                         ii += ParseChar (input, ii, format [fi + 1], allow_white_spaces, out temp_int);
 553                                         if (temp_int == -1)
 554                                                 return false;
 555                                         break;
 556                                 default:
 557                                         //Console.WriteLine ("un-parsed character: {0}", ch);
 558                                         tokLen = 1;
 559                                         ii += ParseChar (input, ii, format [fi], allow_white_spaces, out temp_int);
 560                                         if (temp_int == -1)
 561                                                 return false;
 562                                         break;
 563                                 }
 564                                 fi += tokLen;
 565                         }
 566
 567                         //Console.WriteLine ("{0}-{1}-{2} {3}:{4} {5}", year, month, day, hour, minute, offset);
 568                         if (offset == TimeSpan.MinValue && (styles & DateTimeStyles.AssumeLocal) != 0)
 569                                 offset = TimeZone.CurrentTimeZone.GetUtcOffset (DateTime.Now);
 570
 571                         if (offset == TimeSpan.MinValue && (styles & DateTimeStyles.AssumeUniversal) != 0)
 572                                 offset = TimeSpan.Zero;
 573
 574                         if (hour < 0)           hour = 0;
 575                         if (minute < 0)         minute = 0;
 576                         if (second < 0)         second = 0;
 577                         if (fraction < 0)       fraction = 0;
 578                         if (year > 0 && month > 0 && day > 0) {
 579                                 result = new DateTimeOffset (year, month, day, hour, minute, second, (int) (1000 * fraction), offset);
 580                                 if ((styles & DateTimeStyles.AdjustToUniversal) != 0)
 581                                         result = result.ToUniversalTime ();
 582                                 return true;
 583                         }
 584
 585                         return false;
 586                 }
 587
 588                 private static int ParseNumber (string input, int pos, int digits, bool leading_zero, bool allow_leading_white, out int result)
 589                 {
 590                         int digit_parsed;
 591                         return ParseNumber (input, pos, digits, leading_zero, allow_leading_white, out result, out digit_parsed);
 592                 }
 593
 594                 private static int ParseNumber (string input, int pos, int digits, bool leading_zero, bool allow_leading_white, out int result, out int digit_parsed)
 595                 {
 596                         int char_parsed = 0;
 597                         digit_parsed = 0;
 598                         result = 0;
 599                         for (; allow_leading_white && pos < input.Length && input[pos] == ' '; pos++)
 600                                 char_parsed++;
 601
 602                         for (; pos < input.Length && Char.IsDigit (input[pos]) && digits > 0; pos ++, char_parsed++, digit_parsed++, digits --)
 603                                 result = 10 * result + (byte) (input[pos] - '0');
 604
 605                         if (leading_zero && digits > 0)
 606                                 result = -1;
 607
 608                         if (digit_parsed == 0)
 609                                 result = -1;
 610
 611                         return char_parsed;
 612                 }
 613
 614                 private static int ParseEnum (string input, int pos, string [] enums, bool allow_leading_white, out int result)
 615                 {
 616                         int char_parsed = 0;
 617                         result = -1;
 618                         for (; allow_leading_white && pos < input.Length && input[pos] == ' '; pos++)
 619                                 char_parsed ++;
 620
 621                         for (int i = 0; i < enums.Length; i++)
 622                                 if (input.Substring(pos).StartsWith (enums [i])) {
 623                                         result = i;
 624                                         break;
 625                                 }
 626
 627                         if (result >= 0)
 628                                 char_parsed += enums[result].Length;
 629
 630                         return char_parsed;
 631                 }
 632
 633                 private static int ParseChar (string input, int pos, char c, bool allow_leading_white, out int result)
 634                 {
 635                         int char_parsed = 0;
 636                         result = -1;
 637                         for (; allow_leading_white && pos < input.Length && input[pos] == ' '; pos++, char_parsed++)
 638                                 ;
 639
 640                         if (pos < input.Length && input[pos] == c){
 641                                 result = (int) c;
 642                                 char_parsed ++;
 643                         }
 644
 645                         return char_parsed;
 646                 }
 647
 648                 public TimeSpan Subtract (DateTimeOffset value)
 649                 {
 650                         return UtcDateTime - value.UtcDateTime;
 651                 }
 652
 653                 public DateTimeOffset Subtract (TimeSpan value)
 654                 {
 655                         return Add (-value);
 656                 }
 657
 658                 public static TimeSpan operator - (DateTimeOffset left, DateTimeOffset right)
 659                 {
 660                         return left.Subtract (right);
 661                 }
 662
 663                 public static DateTimeOffset operator - (DateTimeOffset dateTimeTz, TimeSpan timeSpan)
 664                 {
 665                         return dateTimeTz.Subtract (timeSpan);
 666                 }
 667
 668                 public long ToFileTime ()
 669                 {
 670                         return UtcDateTime.ToFileTime ();
 671                 }
 672
 673                 public DateTimeOffset ToLocalTime ()
 674                 {
 675                         return new DateTimeOffset (UtcDateTime.ToLocalTime (), TimeZone.CurrentTimeZone.GetUtcOffset (UtcDateTime.ToLocalTime ()));
 676                 }
 677
 678                 public DateTimeOffset ToOffset (TimeSpan offset)
 679                 {
 680                         return new DateTimeOffset (dt - utc_offset + offset, offset);
 681                 }
 682
 683                 public override string ToString ()
 684                 {
 685                         return ToString (null, null);
 686                 }
 687
 688                 public string ToString (IFormatProvider formatProvider)
 689                 {
 690                         return ToString (null, formatProvider);
 691                 }
 692
 693                 public string ToString (string format)
 694                 {
 695                         return ToString (format, null);
 696                 }
 697
 698                 public string ToString (string format, IFormatProvider formatProvider)
 699                 {
 700                         DateTimeFormatInfo dfi = DateTimeFormatInfo.GetInstance(formatProvider);
 701
 702                         if (format == null || format == String.Empty)
 703                                 format = dfi.ShortDatePattern + " " + dfi.LongTimePattern + " zzz";
 704
 705                         bool to_utc = false, use_invariant = false;
 706                         if (format.Length == 1) {
 707                                 char fchar = format [0];
 708                                 try {
 709                                         format = DateTimeUtils.GetStandardPattern (fchar, dfi, out to_utc, out use_invariant, true);
 710                                 } catch {
 711                                         format = null;
 712                                 }
 713
 714                                 if (format == null)
 715                                         throw new FormatException ("format is not one of the format specifier characters defined for DateTimeFormatInfo");
 716                         }
 717                         return to_utc ? DateTimeUtils.ToString (UtcDateTime, TimeSpan.Zero, format, dfi) : DateTimeUtils.ToString (DateTime, Offset, format, dfi);
 718                 }
 719
 720                 public DateTimeOffset ToUniversalTime ()
 721                 {
 722                         return new DateTimeOffset (UtcDateTime, TimeSpan.Zero);
 723                 }
 724
 725                 public static bool TryParse (string input, out DateTimeOffset result)
 726                 {
 727                         try {
 728                                 result = Parse (input);
 729                                 return true;
 730                         } catch {
 731                                 result = MinValue;
 732                                 return false;
 733                         }
 734                 }
 735
 736                 public static bool TryParse (string input, IFormatProvider formatProvider, DateTimeStyles styles, out DateTimeOffset result)
 737                 {
 738                         try {
 739                                 result = Parse (input, formatProvider, styles);
 740                                 return true;
 741                         } catch {
 742                                 result = MinValue;
 743                                 return false;
 744                         }
 745                 }
 746
 747                 public static bool TryParseExact (string input, string format, IFormatProvider formatProvider, DateTimeStyles styles, out DateTimeOffset result)
 748                 {
 749                         try {
 750                                 result = ParseExact (input, format, formatProvider, styles);
 751                                 return true;
 752                         } catch {
 753                                 result = MinValue;
 754                                 return false;
 755                         }
 756                 }
 757
 758                 public static bool TryParseExact (string input, string[] formats, IFormatProvider formatProvider, DateTimeStyles styles, out DateTimeOffset result)
 759                 {
 760                         try {
 761                                 result = ParseExact (input, formats, formatProvider, styles);
 762                                 return true;
 763                         } catch {
 764                                 result = MinValue;
 765                                 return false;
 766                         }
 767                 }
 768
 769                 public DateTime Date {
 770                         get { return DateTime.SpecifyKind (dt.Date, DateTimeKind.Unspecified); }
 771                 }
 772
 773                 public DateTime DateTime {
 774                         get { return DateTime.SpecifyKind (dt, DateTimeKind.Unspecified); }
 775                 }
 776
 777                 public int Day {
 778                         get { return dt.Day; }
 779                 }
 780
 781                 public DayOfWeek DayOfWeek {
 782                         get { return dt.DayOfWeek; }
 783                 }
 784
 785                 public int DayOfYear {
 786                         get { return dt.DayOfYear; }
 787                 }
 788
 789                 public int Hour {
 790                         get { return dt.Hour; }
 791                 }
 792
 793                 public DateTime LocalDateTime {
 794                         get { return UtcDateTime.ToLocalTime (); }
 795                 }
 796
 797                 public int Millisecond {
 798                         get { return dt.Millisecond; }
 799                 }
 800
 801                 public int Minute {
 802                         get { return dt.Minute; }
 803                 }
 804
 805                 public int Month {
 806                         get { return dt.Month; }
 807                 }
 808
 809                 public static DateTimeOffset Now {
 810                         get { return new DateTimeOffset (DateTime.Now);}
 811                 }
 812
 813                 public TimeSpan Offset {
 814                         get { return utc_offset; }
 815                 }
 816
 817                 public int Second {
 818                         get { return dt.Second; }
 819                 }
 820
 821                 public long Ticks {
 822                         get { return dt.Ticks; }
 823                 }
 824
 825                 public TimeSpan TimeOfDay {
 826                         get { return dt.TimeOfDay; }
 827                 }
 828
 829                 public DateTime UtcDateTime {
 830                         get { return DateTime.SpecifyKind (dt - utc_offset, DateTimeKind.Utc); }
 831                 }
 832
 833                 public static DateTimeOffset UtcNow {
 834                         get { return new DateTimeOffset (DateTime.UtcNow); }
 835                 }
 836
 837                 public long UtcTicks {
 838                         get { return UtcDateTime.Ticks; }
 839                 }
 840
 841                 public int Year {
 842                         get { return dt.Year; }
 843                 }
 844         }
 845 }
 846 #endif