最简单的方法可能是编写一个方法来获得一周的开始。然后你可以从另一个日期中减去一个日期,将天数除以7并加1(使之包含在内)。
个人而言,我会使用Noda Time所有这一切,但使用DateTime
:
// Always uses Monday-to-Sunday weeks
public static DateTime GetStartOfWeek(DateTime input)
{
// Using +6 here leaves Monday as 0, Tuesday as 1 etc.
int dayOfWeek = (((int) input.DayOfWeek) + 6) % 7;
return input.Date.AddDays(-dayOfWeek);
}
public static int GetWeeks(DateTime start, DateTime end)
{
start = GetStartOfWeek(start);
end = GetStartOfWeek(end);
int days = (int) (end - start).TotalDays;
return (days/7) + 1; // Adding 1 to be inclusive
}
完整的示例:
using System;
class Program
{
static void Main (string[] args)
{
ShowWeeks(new DateTime(2016, 9, 17), new DateTime(2016, 9, 26));
ShowWeeks(new DateTime(2016, 9, 17), new DateTime(2016, 9, 25));
ShowWeeks(new DateTime(2016, 9, 19), new DateTime(2016, 9, 26));
ShowWeeks(new DateTime(2016, 9, 12), new DateTime(2016, 9, 25));
}
static void ShowWeeks(DateTime start, DateTime end)
{
int weeks = GetWeeks(start, end);
Console.WriteLine($"{start:d} {end:d} {weeks}");
}
// Always uses Monday-to-Sunday weeks
public static DateTime GetStartOfWeek(DateTime input)
{
// Using +6 here leaves Monday as 0, Tuesday as 1 etc.
int dayOfWeek = (((int) input.DayOfWeek) + 6) % 7;
return input.Date.AddDays(-dayOfWeek);
}
public static int GetWeeks(DateTime start, DateTime end)
{
start = GetStartOfWeek(start);
end = GetStartOfWeek(end);
int days = (int) (end - start).TotalDays;
return (days/7) + 1; // Adding 1 to be inclusive
}
}
输出(在我的英国语言环境):
17/09/2016 26/09/2016 3
17/09/2016 25/09/2016 2
19/09/2016 26/09/2016 2
12/09/2016 25/09/2016 2
@Roy_Dorsthorst:我看不出这将是部分解。这只是格式化 - 它与计算日期之间的差异无关。 –