如何在c#中计算两个日期之间的月差?
c#中是否有相当于VB的DateDiff()方法。我需要找出相隔数年的两个日期之间的月差。文档说我可以像这样使用TimeSpan:
TimeSpan ts = date1 - date2;
但这里的数据是以天为单位的。我不想把这个数字除以30,因为不是每个月都是30天,而且两个操作数的值相差很大,所以我担心除以30可能会得到错误的值。
有什么建议吗?
如何在c#中计算两个日期之间的月差?
c#中是否有相当于VB的DateDiff()方法。我需要找出相隔数年的两个日期之间的月差。文档说我可以像这样使用TimeSpan:
TimeSpan ts = date1 - date2;
但这里的数据是以天为单位的。我不想把这个数字除以30,因为不是每个月都是30天,而且两个操作数的值相差很大,所以我担心除以30可能会得到错误的值。
有什么建议吗?
当前回答
以下是我对获得Months差异的贡献,我发现这是准确的:
namespace System
{
public static class DateTimeExtensions
{
public static Int32 DiffMonths( this DateTime start, DateTime end )
{
Int32 months = 0;
DateTime tmp = start;
while ( tmp < end )
{
months++;
tmp = tmp.AddMonths( 1 );
}
return months;
}
}
}
用法:
Int32 months = DateTime.Now.DiffMonths( DateTime.Now.AddYears( 5 ) );
您可以创建另一个名为DiffYears的方法,并应用与上面完全相同的逻辑,并在while循环中使用AddYears而不是AddMonths。
其他回答
我在VB中检查了这个方法的用法。NET通过MSDN,它似乎有很多用途。c#中没有这样的内置方法。(即使这不是一个好主意)你可以在c#中调用VB。
将Microsoft.VisualBasic.dll添加到 你的项目作为参考 使用 Microsoft.VisualBasic.DateAndTime.DateDiff 在代码中
我对两个日期之间总月差的理解有一个整数部分和一个小数部分(日期很重要)。
积分部分是整个月的差额。
对我来说,小数部分是开始月份和结束月份之间一天的百分比(到一个月的全部天数)的差值。
public static class DateTimeExtensions
{
public static double TotalMonthsDifference(this DateTime from, DateTime to)
{
//Compute full months difference between dates
var fullMonthsDiff = (to.Year - from.Year)*12 + to.Month - from.Month;
//Compute difference between the % of day to full days of each month
var fractionMonthsDiff = ((double)(to.Day-1) / (DateTime.DaysInMonth(to.Year, to.Month)-1)) -
((double)(from.Day-1)/ (DateTime.DaysInMonth(from.Year, from.Month)-1));
return fullMonthsDiff + fractionMonthsDiff;
}
}
有了这个扩展,这些是结果:
2/29/2000 TotalMonthsDifference 2/28/2001 => 12
2/28/2000 TotalMonthsDifference 2/28/2001 => 12.035714285714286
01/01/2000 TotalMonthsDifference 01/16/2000 => 0.5
01/31/2000 TotalMonthsDifference 01/01/2000 => -1.0
01/31/2000 TotalMonthsDifference 02/29/2000 => 1.0
01/31/2000 TotalMonthsDifference 02/28/2000 => 0.9642857142857143
01/31/2001 TotalMonthsDifference 02/28/2001 => 1.0
你可以使用野田时间https://nodatime.org/
LocalDate start = new LocalDate(2010, 1, 5);
LocalDate end = new LocalDate(2012, 6, 1);
Period period = Period.Between(start, end, PeriodUnits.Months);
Console.WriteLine(period.Months);
Public Class ClassDateOperation
Private prop_DifferenceInDay As Integer
Private prop_DifferenceInMonth As Integer
Private prop_DifferenceInYear As Integer
Public Function DayMonthYearFromTwoDate(ByVal DateStart As Date, ByVal DateEnd As Date) As ClassDateOperation
Dim differenceInDay As Integer
Dim differenceInMonth As Integer
Dim differenceInYear As Integer
Dim myDate As Date
DateEnd = DateEnd.AddDays(1)
differenceInYear = DateEnd.Year - DateStart.Year
If DateStart.Month <= DateEnd.Month Then
differenceInMonth = DateEnd.Month - DateStart.Month
Else
differenceInYear -= 1
differenceInMonth = (12 - DateStart.Month) + DateEnd.Month
End If
If DateStart.Day <= DateEnd.Day Then
differenceInDay = DateEnd.Day - DateStart.Day
Else
myDate = CDate("01/" & DateStart.AddMonths(1).Month & "/" & DateStart.Year).AddDays(-1)
If differenceInMonth <> 0 Then
differenceInMonth -= 1
Else
differenceInMonth = 11
differenceInYear -= 1
End If
differenceInDay = myDate.Day - DateStart.Day + DateEnd.Day
End If
prop_DifferenceInDay = differenceInDay
prop_DifferenceInMonth = differenceInMonth
prop_DifferenceInYear = differenceInYear
Return Me
End Function
Public ReadOnly Property DifferenceInDay() As Integer
Get
Return prop_DifferenceInDay
End Get
End Property
Public ReadOnly Property DifferenceInMonth As Integer
Get
Return prop_DifferenceInMonth
End Get
End Property
Public ReadOnly Property DifferenceInYear As Integer
Get
Return prop_DifferenceInYear
End Get
End Property
End Class
我只是需要一些简单的东西来满足例如,只输入月份/年的就业日期,所以希望工作的年份和月份不同。这就是我所使用的,只是为了实用
public static YearsMonths YearMonthDiff(DateTime startDate, DateTime endDate) {
int monthDiff = ((endDate.Year * 12) + endDate.Month) - ((startDate.Year * 12) + startDate.Month) + 1;
int years = (int)Math.Floor((decimal) (monthDiff / 12));
int months = monthDiff % 12;
return new YearsMonths {
TotalMonths = monthDiff,
Years = years,
Months = months
};
}
net小提琴