c# - 从时间段中选择一天 - 重复

Question

我正在尝试为我的日历应用程序实现重复模式。我希望它的工作方式与 Outlook 在您设置重复约会时的工作方式相同。

public async Task<ValidationResponse<ReccurrenceModel>> ApplyReccurrencePeriod (string userName, ReccurrenceModel value)
        {
            var user = await repository.FindByUserName(userName);

            var fromDateUTC = DateTime.SpecifyKind(value.FromDate, DateTimeKind.Utc);
            var toDateUTC = DateTime.SpecifyKind(value.ToDate, DateTimeKind.Utc);

            var dates = new List<DateTime>();
            var weeklyReccurrence = value.weeklyReccurrence;

            if (value.IsMonday == true)
            {
                var fromDate = value.FromDate;
                var toDate = value.ToDate;
                for (var dt = fromDate; dt < toDate; dt = dt.AddDays(1))
                {
                    dates.Add(dt);
                }
                var savedDates = dates.Where(x => x.DayOfWeek == DayOfWeek.Monday).Select(x => x.Date);
            }
// I do the same code to verify every week day 

                var test = dates.Where(x => x.DayOfWeek == DayOfWeek.Friday).Select(x => x.Date);
            }

            foreach (var date in savedDates) {
                var x = user.Holidays.FirstOrDefault(kvp => kvp.Key == date
                                     && kvp.Value.StateVal == value.State.StateVal);

                var dateUTC = DateTime.SpecifyKind(date, DateTimeKind.Utc);

                user.Holidays[dateUTC] = value.State;

            }
            // save
            var updatedUser = await repository.UpdateEmployee(user);
            return await Task.FromResult(new ValidationResponse<HolidayModel>()
            {
                IsValid = true,
                Result = updatedUser.Holidays.ContainsKey(dateUTC) ? new HolidayModel() { Date = dateUTC, State = updatedUser.Holidays[dateUTC] } : null
            });

        }
    }

我的代码的问题是它只有在每周重复时才有效。我需要让它工作才能有 2、3、... n 周的复发。我怎样才能让它跳过几周？

 public class ReccurrenceModel
    {
        public DateTime FromDate { get; set; }
        public DateTime ToDate { get; set; }
        public int WeeklyReccurrence { get; set; }
        public State State { get; set; }
        public bool IsMonday { get; set; }
        public bool IsTuesday { get; set; }
        public bool IsWednesday { get; set; }
        public bool IsThursday { get; set; }
        public bool  IsFriday { get; set; }
        public DateTime FromDateToReturn { get; set; }
        public DateTime ToDateToReturn { get; set; }
    }

Answer 1

代码有点绕，有很多行什么都不做。

在这里，我提供了一个代码示例，尽管一点也不优雅，但可以为您提供所需的行为，以下代码将创建一个每 2、3 周重复一次的天数列表，无论您需要在它的电话。

此方法还接受您要为其创建重复的 DayOfWeek 列表

private static void GetRecurrentDays(DateTime fromDate, DateTime untilDate, uint weeklyRecurrence, List<DayOfWeek> recurrenceDays)
{
    var recurrenceDates = new List<DateTime>();
    for (var dt = fromDate; dt < untilDate; dt = dt.AddDays(1))
    {
        if (recurrenceDays.Any(day => day.Equals(dt.DayOfWeek)))
        {
            var lastDate = 
                recurrenceDates
                    .LastOrDefault(date => date.DayOfWeek.Equals(dt.DayOfWeek));

            // We multiply 7 days (a week) with weeklyRecurrence to 
            // calculate the appropiate date in which to add another day, 
            // calling with either 0 or 1 will calculate a weekly 
            // schedule
            if (lastDate.Equals(DateTime.MinValue) 
                || weeklyRecurrence.Equals(0)
                || ((dt - lastDate).Days % (7 * weeklyRecurrence)).Equals(0) )
            {
                recurrenceDates.Add(dt);
            }
        }
    }
}

您可以将此代码嵌入您的代码中以获取每周重复的日期，然后在您的代码中进一步使用它们