Itenso.TimePeriod.DateDiff.CalcQuarters C# (CSharp) Метод

        private int CalcQuarters()
        {
            if ( TimeCompare.IsSameMonth( date1, date2 ) )
            {
                return 0;
            }

            int year1 = TimeTool.GetYearOf( yearBaseMonth, Year1, Month1 );
            YearQuarter quarter1 = TimeTool.GetQuarterOfMonth( yearBaseMonth, (YearMonth)Month1 );

            int year2 = TimeTool.GetYearOf( yearBaseMonth, Year2, Month2 );
            YearQuarter quarter2 = TimeTool.GetQuarterOfMonth( yearBaseMonth, (YearMonth)Month2 );

            return
                ( ( year2 * TimeSpec.QuartersPerYear ) + quarter2 ) -
                ( ( year1 * TimeSpec.QuartersPerYear ) + quarter1 );
        }