2

想象一下,我有一个名为NextSend表示DateTime值的属性

4/11/2011 10:30:00 AM - Monday

假设我有一个时间表,(Monday)在这种情况下必须每周发送特定日期,所以为了弄清楚下一个每周的时间表,我最终得到了解决方案,我必须检查每个下一个日期的日期,直到DayOfWeek匹配specific day日程安排

4/17 /2011 10:30:00 AM - Monday

有没有其他最好的方法来克服检查每个第二天日期的日期名称?

这是我提到的逻辑:

  int nowYear = DateTime.Now.Year;
  int nowMonth = DateTime.Now.Month;
  int nowDay = DateTime.Now.Day;
  int scheduleHour = this.Schedule.Time.Value.Hour;
  int scheduleMinute = this.Schedule.Time.Value.Minute;
  int scheduleSecond = this.Schedule.Time.Value.Second;
  int scheduleDay = -1;
  if(this.Schedule.Day.HasValue)
      scheduleDay= this.Schedule.Day.Value;

 switch (type)
            {
                case Schedule.ScheduleType.Weekly:
                    bool founded = false;
                    while (!founded)
                    {
                        //Check if last day of the current month
                        if (DateTime.DaysInMonth(nowYear, nowMonth) == nowDay)
                        {
                            //last day at this year, then move to next year
                            if (nowMonth == 12)
                            {
                                nowYear++;
                                nowMonth = 1;
                                nowDay = 1;
                            }
                            //its the end of a month then Move to next month
                            else
                            {
                                nowMonth++;
                                nowDay = 1;
                            }
                        }
                        //Get new proposed date
                        newNextSend = new DateTime(nowYear, nowMonth, nowDay, scheduleHour, scheduleMinute, scheduleSecond);

                        //Check if Next week schedule founded with specific day name
                        if (newNextSend.DayOfWeek ==
                            (DayOfWeek)Enum.Parse(typeof(DayOfWeek), Schedule.daysCalendar[scheduleDay - 1]))
                        {
                            founded = true;
                        }
                        else
                            nowDay++;
                    }
                    break;
}
4

4 回答 4

4

正如所有其他人所说的那样:AddDays(7) 将确保每周计划按要求运行。但是,如果您正在寻找一种方法来找出特定weekday的下一次出现,那么您可以执行以下操作:

private static DateTime GetNextDayOccurrence(DayOfWeek day, DateTime startDate)
{
    if (startDate.DayOfWeek == day)
    {
        return startDate;
    }
    else
    {
        return GetNextDayOccurrence(day, startDate.AddDays(1));
    }
}

然后这样的电话

var nextWednesday = GetNextDayOccurrence(DayOfWeek.Wednesday, DateTime.Today);

将返回星期三的第一次出现。之后每周计划继续运行。如果您需要从下周开始第一次出现“星期三”,请通过

DateTime.Today.AddDays(7) 

到上述方法的“startDate”参数。

于 2011-04-11T11:35:14.543 回答
2

为什么不在原日期上增加 7 天?一周中的天数是恒定的;)

下个星期一:

var nextMonday = thisMonday.AddDays(7);
于 2011-04-11T10:45:17.897 回答
0

你不能使用 AddDays(7) 吗?

例如

DateTime nextSheduleDate = scheduleDateTime.AddDays(7); 

这是托比亚斯答案的非递归版本。使用丹尼尔提到的逻辑。

public static DateTime GetNextDayOccurrence(DateTime startDate, DayOfWeek dayOfWeek)
{
  var offset = startDate.DayOfWeek > dayOfWeek ? 7 : 0;
  var days = (int) dayOfWeek + offset - (int) startDate.DayOfWeek;

  var dateTime = startDate.AddDays(days);
  return dateTime;
}
于 2011-04-11T10:47:44.410 回答
0
  1. 有一个方法调用AddDays可以自动处理月份和年份的换行。
  2. 周总是 7 天。只需添加当前星期几和日程表星期几之间的差异。
于 2011-04-11T10:47:50.700 回答