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@ararog
Created December 2, 2013 14:02
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A C# version of Days360 excel function.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace Project.Helpers
{
public static class DateTimeExtensions
{
public static int Days360(this DateTime? date, DateTime? initialDate)
{
return Days360(date.Value, initialDate.Value);
}
public static int Days360(this DateTime date, DateTime initialDate)
{
var dateA = initialDate;
var dateB = date;
var dayA = dateA.Day;
var dayB = dateB.Day;
if (lastDayOfFebruary(dateA) && lastDayOfFebruary(dateB))
dayB = 30;
if (dayA == 31 && lastDayOfFebruary(dateA))
dayA = 30;
if (dayA == 30 && dayB == 31)
dayB = 30;
int days = (dateB.Year - dateA.Year) * 360 +
((dateB.Month + 1) - (dateA.Month + 1)) * 30 + (dayB - dayA);
return days;
}
private static bool lastDayOfFebruary(DateTime date) {
int lastDay = DateTime.DaysInMonth(date.Year, 2);
return date.Day == lastDay;
}
}
}
@deekumavat
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i guess this will work for you
return ((@endYear-@startYear)_12_30)+((@endMonth-1)-(@startMonth-1))*30+(@endDay-@startDay)

Eg :
starte Date=2014/02/17 and End date =2014/10/08
return ((2014-2014)_12_30)+((10-1)-(2-1))*30+(8-17)

@DanielSmithMichigan
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private static bool lastDayOfFebruary(DateTime date) {

            int lastDay = DateTime.DaysInMonth(date.Year, 2);
    
            return date.Day == lastDay;
        }

I don't write c#, so forgive me if this is just wrong, but: it doesn't look like your lastDayOfFebruary function actually checks if date is in february, only if date.Day is 28/29.

@jairdean
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private static bool lastDayOfFebruary(DateTime date) {

        int lastDay = DateTime.DaysInMonth(date.Year, 2);

        return date.Day == lastDay;
    }

I don't write c#, so forgive me if this is just wrong, but: it doesn't look like your lastDayOfFebruary function actually checks if date is in february, only if date.Day is 28/29.

You're right, the method should be like this:

    private static bool LastDayOfFebruary(DateTime date)
    {
        if (date.Month == 2)
        {
            int lastDay = DateTime.DaysInMonth(date.Year, date.Month);
            return date.Day == lastDay;
        }

        return false;
    }

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