| | | 1 | | // Licensed to the .NET Foundation under one or more agreements. |
| | | 2 | | // The .NET Foundation licenses this file to you under the MIT license. |
| | | 3 | | |
| | | 4 | | namespace System.Globalization |
| | | 5 | | { |
| | | 6 | | // Gregorian Calendars use Era Info |
| | | 7 | | internal sealed class EraInfo |
| | | 8 | | { |
| | | 9 | | internal int era; // The value of the era. |
| | | 10 | | internal long ticks; // The time in ticks when the era starts |
| | | 11 | | internal int yearOffset; // The offset to Gregorian year when the era starts. |
| | | 12 | | // Gregorian Year = Era Year + yearOffset |
| | | 13 | | // Era Year = Gregorian Year - yearOffset |
| | | 14 | | internal int minEraYear; // Min year value in this era. Generally, this value is 1, but this may |
| | | 15 | | // be affected by the DateTime.MinValue; |
| | | 16 | | internal int maxEraYear; // Max year value in this era. (== the year length of the era + 1) |
| | | 17 | | |
| | | 18 | | internal string? eraName; // The era name |
| | | 19 | | internal string? abbrevEraName; // Abbreviated Era Name |
| | | 20 | | internal string? englishEraName; // English era name |
| | | 21 | | |
| | | 22 | | internal EraInfo(int era, int startYear, int startMonth, int startDay, int yearOffset, int minEraYear, int maxEr |
| | | 23 | | { |
| | | 24 | | this.era = era; |
| | | 25 | | this.yearOffset = yearOffset; |
| | | 26 | | this.minEraYear = minEraYear; |
| | | 27 | | this.maxEraYear = maxEraYear; |
| | | 28 | | this.ticks = new DateTime(startYear, startMonth, startDay).Ticks; |
| | | 29 | | } |
| | | 30 | | |
| | | 31 | | internal EraInfo(int era, int startYear, int startMonth, int startDay, int yearOffset, int minEraYear, int maxEr |
| | | 32 | | string eraName, string abbrevEraName, string englishEraName) |
| | | 33 | | { |
| | | 34 | | this.era = era; |
| | | 35 | | this.yearOffset = yearOffset; |
| | | 36 | | this.minEraYear = minEraYear; |
| | | 37 | | this.maxEraYear = maxEraYear; |
| | | 38 | | // codeql[cs/leap-year/unsafe-date-construction-from-two-elements] - A DateTime object is created using valu |
| | | 39 | | this.ticks = new DateTime(startYear, startMonth, startDay).Ticks; |
| | | 40 | | this.eraName = eraName; |
| | | 41 | | this.abbrevEraName = abbrevEraName; |
| | | 42 | | this.englishEraName = englishEraName; |
| | | 43 | | } |
| | | 44 | | } |
| | | 45 | | |
| | | 46 | | // This calendar recognizes two era values: |
| | | 47 | | // 0 CurrentEra (AD) |
| | | 48 | | // 1 BeforeCurrentEra (BC) |
| | | 49 | | internal sealed class GregorianCalendarHelper |
| | | 50 | | { |
| | | 51 | | // |
| | | 52 | | // This is the max Gregorian year can be represented by DateTime class. The limitation |
| | | 53 | | // is derived from DateTime class. |
| | | 54 | | // |
| | 0 | 55 | | internal int MaxYear => m_maxYear; |
| | | 56 | | |
| | | 57 | | private readonly int m_maxYear; |
| | | 58 | | private readonly int m_minYear; |
| | | 59 | | private readonly Calendar m_Cal; |
| | | 60 | | private readonly EraInfo[] m_EraInfo; |
| | | 61 | | private readonly long _minSupportedTicks; |
| | | 62 | | private readonly long _maxSupportedTicks; |
| | | 63 | | |
| | | 64 | | // Construct an instance of gregorian calendar. |
| | 0 | 65 | | internal GregorianCalendarHelper(Calendar cal, EraInfo[] eraInfo) |
| | | 66 | | { |
| | 0 | 67 | | m_Cal = cal; |
| | 0 | 68 | | m_EraInfo = eraInfo; |
| | 0 | 69 | | m_maxYear = eraInfo[0].maxEraYear; |
| | 0 | 70 | | m_minYear = eraInfo[0].minEraYear; |
| | 0 | 71 | | _minSupportedTicks = cal.MinSupportedDateTime.Ticks; |
| | 0 | 72 | | _maxSupportedTicks = cal.MaxSupportedDateTime.Ticks; |
| | 0 | 73 | | } |
| | | 74 | | |
| | | 75 | | // EraInfo.yearOffset: The offset to Gregorian year when the era starts. Gregorian Year = Era Year + yearOffset |
| | | 76 | | // Era Year = Gregorian Year - yearOffset |
| | | 77 | | // EraInfo.minEraYear: Min year value in this era. Generally, this value is 1, but this may be affected by the |
| | | 78 | | // EraInfo.maxEraYear: Max year value in this era. (== the year length of the era + 1) |
| | | 79 | | private int GetYearOffset(int year, int era, bool throwOnError) |
| | | 80 | | { |
| | 0 | 81 | | if (year < 0) |
| | | 82 | | { |
| | 0 | 83 | | if (throwOnError) |
| | | 84 | | { |
| | 0 | 85 | | throw new ArgumentOutOfRangeException(nameof(year), SR.ArgumentOutOfRange_NeedNonNegNum); |
| | | 86 | | } |
| | 0 | 87 | | return -1; |
| | | 88 | | } |
| | | 89 | | |
| | 0 | 90 | | if (era == Calendar.CurrentEra) |
| | | 91 | | { |
| | 0 | 92 | | era = m_Cal.CurrentEraValue; |
| | | 93 | | } |
| | | 94 | | |
| | 0 | 95 | | var eras = m_EraInfo; |
| | 0 | 96 | | for (int i = 0; i < eras.Length; i++) |
| | | 97 | | { |
| | 0 | 98 | | EraInfo eraInfo = eras[i]; |
| | 0 | 99 | | if (era == eraInfo.era) |
| | | 100 | | { |
| | 0 | 101 | | if (year >= eraInfo.minEraYear) |
| | | 102 | | { |
| | 0 | 103 | | if (year <= eraInfo.maxEraYear) |
| | | 104 | | { |
| | 0 | 105 | | return eraInfo.yearOffset; |
| | | 106 | | } |
| | 0 | 107 | | else if (!LocalAppContextSwitches.EnforceJapaneseEraYearRanges) |
| | | 108 | | { |
| | | 109 | | // If we got the year number exceeding the era max year number, this still possible be valid |
| | | 110 | | // introducing new eras after the era we are checking. we'll loop on the eras after the era |
| | | 111 | | // can exist in one of these eras. otherwise, we'll throw. |
| | | 112 | | // Note, we always return the offset associated with the requested era. |
| | | 113 | | // |
| | | 114 | | // Here is some example: |
| | | 115 | | // if we are getting the era number 4 (Heisei) and getting the year number 32. if the era 4 |
| | | 116 | | // then year 32 exceeded the range of era 4 and we'll try to find out if the years differenc |
| | | 117 | | // the subsequent eras (e.g era 5 and up) |
| | | 118 | | |
| | 0 | 119 | | int remainingYears = year - eraInfo.maxEraYear; |
| | | 120 | | |
| | 0 | 121 | | for (int j = i - 1; j >= 0; j--) |
| | | 122 | | { |
| | 0 | 123 | | if (remainingYears <= eras[j].maxEraYear) |
| | | 124 | | { |
| | 0 | 125 | | return eraInfo.yearOffset; |
| | | 126 | | } |
| | 0 | 127 | | remainingYears -= eras[j].maxEraYear; |
| | | 128 | | } |
| | | 129 | | } |
| | | 130 | | } |
| | | 131 | | |
| | 0 | 132 | | if (throwOnError) |
| | | 133 | | { |
| | 0 | 134 | | throw new ArgumentOutOfRangeException( |
| | 0 | 135 | | nameof(year), |
| | 0 | 136 | | SR.Format( |
| | 0 | 137 | | SR.ArgumentOutOfRange_Range, |
| | 0 | 138 | | eraInfo.minEraYear, |
| | 0 | 139 | | eraInfo.maxEraYear)); |
| | | 140 | | } |
| | | 141 | | |
| | | 142 | | break; // no need to iterate more on eras. |
| | | 143 | | } |
| | | 144 | | } |
| | | 145 | | |
| | 0 | 146 | | if (throwOnError) |
| | | 147 | | { |
| | 0 | 148 | | throw new ArgumentOutOfRangeException(nameof(era), SR.ArgumentOutOfRange_InvalidEraValue); |
| | | 149 | | } |
| | 0 | 150 | | return -1; |
| | | 151 | | } |
| | | 152 | | |
| | | 153 | | /*=================================GetGregorianYear========================== |
| | | 154 | | **Action: Get the Gregorian year value for the specified year in an era. |
| | | 155 | | **Returns: The Gregorian year value. |
| | | 156 | | **Arguments: |
| | | 157 | | ** year the year value in Japanese calendar |
| | | 158 | | ** era the Japanese emperor era value. |
| | | 159 | | **Exceptions: |
| | | 160 | | ** ArgumentOutOfRangeException if year value is invalid or era value is invalid. |
| | | 161 | | ============================================================================*/ |
| | | 162 | | |
| | | 163 | | internal int GetGregorianYear(int year, int era) |
| | | 164 | | { |
| | 0 | 165 | | return GetYearOffset(year, era, throwOnError: true) + year; |
| | | 166 | | } |
| | | 167 | | |
| | | 168 | | internal bool IsValidYear(int year, int era) |
| | | 169 | | { |
| | 0 | 170 | | return GetYearOffset(year, era, throwOnError: false) >= 0; |
| | | 171 | | } |
| | | 172 | | |
| | | 173 | | internal void CheckTicksRange(long ticks) |
| | | 174 | | { |
| | 0 | 175 | | if (ticks < _minSupportedTicks || ticks > _maxSupportedTicks) ThrowOutOfRange(); |
| | | 176 | | |
| | | 177 | | void ThrowOutOfRange() |
| | | 178 | | { |
| | 0 | 179 | | throw new ArgumentOutOfRangeException( |
| | 0 | 180 | | "time", |
| | 0 | 181 | | SR.Format( |
| | 0 | 182 | | CultureInfo.InvariantCulture, |
| | 0 | 183 | | SR.ArgumentOutOfRange_CalendarRange, |
| | 0 | 184 | | m_Cal.MinSupportedDateTime, |
| | 0 | 185 | | m_Cal.MaxSupportedDateTime)); |
| | | 186 | | } |
| | 0 | 187 | | } |
| | | 188 | | |
| | | 189 | | // Returns the DateTime resulting from adding the given number of |
| | | 190 | | // months to the specified DateTime. The result is computed by incrementing |
| | | 191 | | // (or decrementing) the year and month parts of the specified DateTime by |
| | | 192 | | // value months, and, if required, adjusting the day part of the |
| | | 193 | | // resulting date downwards to the last day of the resulting month in the |
| | | 194 | | // resulting year. The time-of-day part of the result is the same as the |
| | | 195 | | // time-of-day part of the specified DateTime. |
| | | 196 | | // |
| | | 197 | | // In more precise terms, considering the specified DateTime to be of the |
| | | 198 | | // form y / m / d + t, where y is the |
| | | 199 | | // year, m is the month, d is the day, and t is the |
| | | 200 | | // time-of-day, the result is y1 / m1 / d1 + t, |
| | | 201 | | // where y1 and m1 are computed by adding value months |
| | | 202 | | // to y and m, and d1 is the largest value less than |
| | | 203 | | // or equal to d that denotes a valid day in month m1 of year |
| | | 204 | | // y1. |
| | | 205 | | // |
| | | 206 | | public DateTime AddMonths(DateTime time, int months) |
| | | 207 | | { |
| | 0 | 208 | | if (months < -120000 || months > 120000) |
| | | 209 | | { |
| | 0 | 210 | | throw new ArgumentOutOfRangeException( |
| | 0 | 211 | | nameof(months), |
| | 0 | 212 | | SR.Format( |
| | 0 | 213 | | SR.ArgumentOutOfRange_Range, |
| | 0 | 214 | | -120000, |
| | 0 | 215 | | 120000)); |
| | | 216 | | } |
| | 0 | 217 | | CheckTicksRange(time.Ticks); |
| | | 218 | | |
| | 0 | 219 | | time.GetDate(out int y, out int m, out int d); |
| | 0 | 220 | | int i = m - 1 + months; |
| | 0 | 221 | | if (i >= 0) |
| | | 222 | | { |
| | 0 | 223 | | m = i % 12 + 1; |
| | 0 | 224 | | y += i / 12; |
| | | 225 | | } |
| | | 226 | | else |
| | | 227 | | { |
| | 0 | 228 | | m = 12 + (i + 1) % 12; |
| | 0 | 229 | | y += (i - 11) / 12; |
| | | 230 | | } |
| | 0 | 231 | | ReadOnlySpan<int> daysArray = (y % 4 == 0 && (y % 100 != 0 || y % 400 == 0)) ? GregorianCalendar.DaysToMonth |
| | 0 | 232 | | int days = (daysArray[m] - daysArray[m - 1]); |
| | | 233 | | |
| | 0 | 234 | | if (d > days) |
| | | 235 | | { |
| | 0 | 236 | | d = days; |
| | | 237 | | } |
| | 0 | 238 | | long ticks = GregorianCalendar.DateToTicks(y, m, d) + time.TimeOfDay.Ticks; |
| | 0 | 239 | | Calendar.CheckAddResult(ticks, m_Cal.MinSupportedDateTime, m_Cal.MaxSupportedDateTime); |
| | 0 | 240 | | return new DateTime(ticks); |
| | | 241 | | } |
| | | 242 | | |
| | | 243 | | // Returns the DateTime resulting from adding the given number of |
| | | 244 | | // years to the specified DateTime. The result is computed by incrementing |
| | | 245 | | // (or decrementing) the year part of the specified DateTime by value |
| | | 246 | | // years. If the month and day of the specified DateTime is 2/29, and if the |
| | | 247 | | // resulting year is not a leap year, the month and day of the resulting |
| | | 248 | | // DateTime becomes 2/28. Otherwise, the month, day, and time-of-day |
| | | 249 | | // parts of the result are the same as those of the specified DateTime. |
| | | 250 | | // |
| | | 251 | | public DateTime AddYears(DateTime time, int years) |
| | | 252 | | { |
| | 0 | 253 | | return AddMonths(time, years * 12); |
| | | 254 | | } |
| | | 255 | | |
| | | 256 | | // Returns the day-of-month part of the specified DateTime. The returned |
| | | 257 | | // value is an integer between 1 and 31. |
| | | 258 | | // |
| | | 259 | | public int GetDayOfMonth(DateTime time) |
| | | 260 | | { |
| | 0 | 261 | | CheckTicksRange(time.Ticks); |
| | 0 | 262 | | return time.Day; |
| | | 263 | | } |
| | | 264 | | |
| | | 265 | | // Returns the day-of-week part of the specified DateTime. The returned value |
| | | 266 | | // is an integer between 0 and 6, where 0 indicates Sunday, 1 indicates |
| | | 267 | | // Monday, 2 indicates Tuesday, 3 indicates Wednesday, 4 indicates |
| | | 268 | | // Thursday, 5 indicates Friday, and 6 indicates Saturday. |
| | | 269 | | // |
| | | 270 | | public DayOfWeek GetDayOfWeek(DateTime time) |
| | | 271 | | { |
| | 0 | 272 | | CheckTicksRange(time.Ticks); |
| | 0 | 273 | | return time.DayOfWeek; |
| | | 274 | | } |
| | | 275 | | |
| | | 276 | | // Returns the day-of-year part of the specified DateTime. The returned value |
| | | 277 | | // is an integer between 1 and 366. |
| | | 278 | | // |
| | | 279 | | public int GetDayOfYear(DateTime time) |
| | | 280 | | { |
| | 0 | 281 | | CheckTicksRange(time.Ticks); |
| | 0 | 282 | | return time.DayOfYear; |
| | | 283 | | } |
| | | 284 | | |
| | | 285 | | // Returns the number of days in the month given by the year and |
| | | 286 | | // month arguments. |
| | | 287 | | // |
| | | 288 | | public int GetDaysInMonth(int year, int month, int era) |
| | | 289 | | { |
| | | 290 | | // |
| | | 291 | | // Convert year/era value to Gregorain year value. |
| | | 292 | | // |
| | 0 | 293 | | year = GetGregorianYear(year, era); |
| | 0 | 294 | | if (month < 1 || month > 12) |
| | | 295 | | { |
| | 0 | 296 | | ThrowHelper.ThrowArgumentOutOfRange_Month(month); |
| | | 297 | | } |
| | 0 | 298 | | ReadOnlySpan<int> days = ((year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)) ? GregorianCalendar.DaysTo |
| | 0 | 299 | | return days[month] - days[month - 1]; |
| | | 300 | | } |
| | | 301 | | |
| | | 302 | | // Returns the number of days in the year given by the year argument for the current era. |
| | | 303 | | // |
| | | 304 | | |
| | | 305 | | public int GetDaysInYear(int year, int era) |
| | | 306 | | { |
| | | 307 | | // |
| | | 308 | | // Convert year/era value to Gregorain year value. |
| | | 309 | | // |
| | 0 | 310 | | year = GetGregorianYear(year, era); |
| | 0 | 311 | | return (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)) ? 366 : 365; |
| | | 312 | | } |
| | | 313 | | |
| | | 314 | | // Returns the era for the specified DateTime value. |
| | | 315 | | public int GetEra(DateTime time) |
| | | 316 | | { |
| | 0 | 317 | | long ticks = time.Ticks; |
| | | 318 | | // The assumption here is that m_EraInfo is listed in reverse order. |
| | 0 | 319 | | foreach (EraInfo eraInfo in m_EraInfo) |
| | | 320 | | { |
| | 0 | 321 | | if (ticks >= eraInfo.ticks) |
| | | 322 | | { |
| | 0 | 323 | | return eraInfo.era; |
| | | 324 | | } |
| | | 325 | | } |
| | 0 | 326 | | throw new ArgumentOutOfRangeException(nameof(time), SR.ArgumentOutOfRange_Era); |
| | | 327 | | } |
| | | 328 | | |
| | | 329 | | public int[] Eras |
| | | 330 | | { |
| | | 331 | | get |
| | | 332 | | { |
| | 0 | 333 | | EraInfo[] eraInfo = m_EraInfo; |
| | 0 | 334 | | var eras = new int[eraInfo.Length]; |
| | 0 | 335 | | for (int i = 0; i < eraInfo.Length; i++) |
| | | 336 | | { |
| | 0 | 337 | | eras[i] = eraInfo[i].era; |
| | | 338 | | } |
| | 0 | 339 | | return eras; |
| | | 340 | | } |
| | | 341 | | } |
| | | 342 | | |
| | | 343 | | // Returns the month part of the specified DateTime. The returned value is an |
| | | 344 | | // integer between 1 and 12. |
| | | 345 | | // |
| | | 346 | | public int GetMonth(DateTime time) |
| | | 347 | | { |
| | 0 | 348 | | CheckTicksRange(time.Ticks); |
| | 0 | 349 | | return time.Month; |
| | | 350 | | } |
| | | 351 | | |
| | | 352 | | // Returns the number of months in the specified year and era. |
| | | 353 | | // Always return 12. |
| | | 354 | | public int GetMonthsInYear(int year, int era) |
| | | 355 | | { |
| | 0 | 356 | | ValidateYearInEra(year, era); |
| | 0 | 357 | | return 12; |
| | | 358 | | } |
| | | 359 | | |
| | | 360 | | // Returns the year part of the specified DateTime. The returned value is an |
| | | 361 | | // integer between 1 and 9999. |
| | | 362 | | // |
| | | 363 | | public int GetYear(DateTime time) |
| | | 364 | | { |
| | 0 | 365 | | long ticks = time.Ticks; |
| | 0 | 366 | | CheckTicksRange(ticks); |
| | 0 | 367 | | foreach (EraInfo eraInfo in m_EraInfo) |
| | | 368 | | { |
| | 0 | 369 | | if (ticks >= eraInfo.ticks) |
| | | 370 | | { |
| | 0 | 371 | | return time.Year - eraInfo.yearOffset; |
| | | 372 | | } |
| | | 373 | | } |
| | 0 | 374 | | throw new ArgumentException(SR.Argument_NoEra); |
| | | 375 | | } |
| | | 376 | | |
| | | 377 | | // Returns the year that match the specified Gregorian year. The returned value is an |
| | | 378 | | // integer between 1 and 9999. |
| | | 379 | | // |
| | | 380 | | public int GetYear(int year, DateTime time) |
| | | 381 | | { |
| | 0 | 382 | | long ticks = time.Ticks; |
| | 0 | 383 | | foreach (EraInfo eraInfo in m_EraInfo) |
| | | 384 | | { |
| | | 385 | | // while calculating dates with JapaneseLuniSolarCalendar, we can run into cases right after the start o |
| | | 386 | | // and still belong to the month which is started in previous era. Calculating equivalent calendar date |
| | | 387 | | // using the new era info which will have the year offset equal to the year we are calculating year = m_ |
| | | 388 | | // which will end up with zero as calendar year. |
| | | 389 | | // We should use the previous era info instead to get the right year number. Example of such date is Feb |
| | 0 | 390 | | if (ticks >= eraInfo.ticks && year > eraInfo.yearOffset) |
| | | 391 | | { |
| | 0 | 392 | | return year - eraInfo.yearOffset; |
| | | 393 | | } |
| | | 394 | | } |
| | 0 | 395 | | throw new ArgumentException(SR.Argument_NoEra); |
| | | 396 | | } |
| | | 397 | | |
| | | 398 | | // Checks whether a given day in the specified era is a leap day. This method returns true if |
| | | 399 | | // the date is a leap day, or false if not. |
| | | 400 | | // |
| | | 401 | | public bool IsLeapDay(int year, int month, int day, int era) |
| | | 402 | | { |
| | | 403 | | // year/month/era checking is done in GetDaysInMonth() |
| | 0 | 404 | | if (day < 1 || day > GetDaysInMonth(year, month, era)) |
| | | 405 | | { |
| | 0 | 406 | | throw new ArgumentOutOfRangeException( |
| | 0 | 407 | | nameof(day), |
| | 0 | 408 | | SR.Format( |
| | 0 | 409 | | SR.ArgumentOutOfRange_Range, |
| | 0 | 410 | | 1, |
| | 0 | 411 | | GetDaysInMonth(year, month, era))); |
| | | 412 | | } |
| | | 413 | | |
| | 0 | 414 | | if (!IsLeapYear(year, era)) |
| | | 415 | | { |
| | 0 | 416 | | return false; |
| | | 417 | | } |
| | | 418 | | |
| | 0 | 419 | | if (month == 2 && day == 29) |
| | | 420 | | { |
| | 0 | 421 | | return true; |
| | | 422 | | } |
| | | 423 | | |
| | 0 | 424 | | return false; |
| | | 425 | | } |
| | | 426 | | |
| | | 427 | | // Giving the calendar year and era, ValidateYearInEra will validate the existence of the input year in the inpu |
| | | 428 | | // This method will throw if the year or the era is invalid. |
| | 0 | 429 | | public void ValidateYearInEra(int year, int era) => GetYearOffset(year, era, throwOnError: true); |
| | | 430 | | |
| | | 431 | | // Returns the leap month in a calendar year of the specified era. |
| | | 432 | | // This method always returns 0 as all calendars using this method don't have leap months. |
| | | 433 | | public int GetLeapMonth(int year, int era) |
| | | 434 | | { |
| | 0 | 435 | | ValidateYearInEra(year, era); |
| | 0 | 436 | | return 0; |
| | | 437 | | } |
| | | 438 | | |
| | | 439 | | // Checks whether a given month in the specified era is a leap month. |
| | | 440 | | // This method always returns false as all calendars using this method don't have leap months. |
| | | 441 | | public bool IsLeapMonth(int year, int month, int era) |
| | | 442 | | { |
| | 0 | 443 | | ValidateYearInEra(year, era); |
| | 0 | 444 | | if (month < 1 || month > 12) |
| | | 445 | | { |
| | 0 | 446 | | throw new ArgumentOutOfRangeException( |
| | 0 | 447 | | nameof(month), |
| | 0 | 448 | | SR.Format( |
| | 0 | 449 | | SR.ArgumentOutOfRange_Range, |
| | 0 | 450 | | 1, |
| | 0 | 451 | | 12)); |
| | | 452 | | } |
| | 0 | 453 | | return false; |
| | | 454 | | } |
| | | 455 | | |
| | | 456 | | // Checks whether a given year in the specified era is a leap year. This method returns true if |
| | | 457 | | // year is a leap year, or false if not. |
| | | 458 | | // |
| | | 459 | | public bool IsLeapYear(int year, int era) |
| | | 460 | | { |
| | 0 | 461 | | year = GetGregorianYear(year, era); |
| | 0 | 462 | | return year % 4 == 0 && (year % 100 != 0 || year % 400 == 0); |
| | | 463 | | } |
| | | 464 | | |
| | | 465 | | // Returns the date and time converted to a DateTime value. Throws an exception if the n-tuple is invalid. |
| | | 466 | | // |
| | | 467 | | public DateTime ToDateTime(int year, int month, int day, int hour, int minute, int second, int millisecond, int |
| | | 468 | | { |
| | 0 | 469 | | year = GetGregorianYear(year, era); |
| | 0 | 470 | | long ticks = GregorianCalendar.DateToTicks(year, month, day) + Calendar.TimeToTicks(hour, minute, second, mi |
| | 0 | 471 | | CheckTicksRange(ticks); |
| | 0 | 472 | | return new DateTime(ticks); |
| | | 473 | | } |
| | | 474 | | |
| | | 475 | | public int GetWeekOfYear(DateTime time, CalendarWeekRule rule, DayOfWeek firstDayOfWeek) |
| | | 476 | | { |
| | 0 | 477 | | CheckTicksRange(time.Ticks); |
| | | 478 | | // Use GregorianCalendar to get around the problem that the implementation in Calendar.GetWeekOfYear() |
| | | 479 | | // can call GetYear() that exceeds the supported range of the Gregorian-based calendars. |
| | 0 | 480 | | return GregorianCalendar.GetDefaultInstance().GetWeekOfYear(time, rule, firstDayOfWeek); |
| | | 481 | | } |
| | | 482 | | |
| | | 483 | | public int ToFourDigitYear(int year, int twoDigitYearMax) |
| | | 484 | | { |
| | 0 | 485 | | ArgumentOutOfRangeException.ThrowIfNegative(year); |
| | | 486 | | |
| | 0 | 487 | | if (year < 100) |
| | | 488 | | { |
| | 0 | 489 | | return (twoDigitYearMax / 100 - (year > twoDigitYearMax % 100 ? 1 : 0)) * 100 + year; |
| | | 490 | | } |
| | | 491 | | |
| | 0 | 492 | | if (year < m_minYear || year > m_maxYear) |
| | | 493 | | { |
| | 0 | 494 | | throw new ArgumentOutOfRangeException( |
| | 0 | 495 | | nameof(year), |
| | 0 | 496 | | SR.Format(SR.ArgumentOutOfRange_Range, m_minYear, m_maxYear)); |
| | | 497 | | } |
| | | 498 | | |
| | | 499 | | // If the year value is above 100, just return the year value. Don't have to do |
| | | 500 | | // the TwoDigitYearMax comparison. |
| | 0 | 501 | | return year; |
| | | 502 | | } |
| | | 503 | | } |
| | | 504 | | } |
| | | 505 | | |