在C＃中计算重复日期的正确方法

在我的项目中，我需要计算重复事件的日期。 一开始我只有一个开始日期/时间以及该事件必须重复的信息：

Every Day Every Week Every 2 Weeks Every 3 Weeks Every Month Every 2 Months ... 

这样做的正确方法是什么？ 它应该可以正常使用不同的时区和日节省时间设置。 我想我应该将日/周/月添加到本地DateTime，然后将其转换为UTC。 但我不确定这一点。 如果我添加几天会发生什么，这将是我们需要向前调整我们的时钟一小时的时间。 在这种情况下，此时间不存在。

下面是我写的代码，但我不确定它在每种情况下都能正常工作：

 private static List FindOccurrences(DateTime localStart, Repeat repeat, int occurrences) { var result = new List { localStart }; switch (repeat) { case Repeat.Daily: for (int i = 1; i <= occurrences; i++) result.Add(localStart.AddDays(i)); break; case Repeat.Every2Weeks: for (int i = 1; i <= occurrences; i++) result.Add(localStart.AddDays((7 * 2) * i)); break; ... } return result; } public List CreateRepeating(string timeZone, Repeat repeat, int repeatEnds, DateTime localStart, int eventDuration) { var events = new List(); var occurrences = FindOccurrences(localStart, repeat, repeatEnds); foreach (var occurrence in occurrences) { var item = new Event(); item.Start = occurrence.ToUtcTime(timeZone); item.End = occurrence.ToUtcTime(timeZone).AddMinutes(eventDuration); events.Add(item); } return events; } 

PS：所有日期都以UTC格式存储在数据库中。

  public enum TimePeriod { None = 0, Day = 1, // Just week, no "two weeks, three weeks etc." Week = 2, Month = 3 } public static class Occurrencies { // May be you want to convert it to method extension: "this DateTime from" public static IEnumerable FindInterval(DateTime from, TimePeriod period, int count) { while (true) { switch (period) { case TimePeriod.Day: from = from.AddDays(count); break; case TimePeriod.Week: from = from.AddDays(7 * count); break; case TimePeriod.Month: from = from.AddMonths(count); break; } yield return from; } } } 

  // Get 5 2-week intervals List intervals2Weeks = Occurrencies .FindInterval(DateTime.Now, TimePeriod.Week, 2) .Take(5) .ToList(); // Get 11 3-month intervals List intervals3Months = Occurrencies .FindInterval(DateTime.Now, TimePeriod.Month, 3) .Take(11) .ToList();