How to calculate the next business days in C#?

There are cases when according to a business day(Monday to Friday) and number of days you have to return the computed business day. Of course the result can not be on week-end.
So if you ever encounter this scenario when you have a certain date and you want to add x days to it and then return the dateTime found you could use the next extension.
I admit that this extension is a very basic solution. I refer to the fact that I don't take into consideration holidays. If you want a more complex solution then you could go to Dynamic-Holiday-Date-Calculator. Or you could create a list of holidays and then make another method - IsHoliday() that should check if a certain date is part of your holiday calendar.

The idea of this algorithm is simple. In a while block we add one day to our original date time and as long as the result date is not in weekend we decrease number of bussiness days to add.

 
        ///

        /// Adds business days to a date
        /// 
        /// 
        /// 
        /// 
        public static DateTime AddBusinessDays(this DateTime dateTime, int businessDays)
        {
            DateTime resultDate = dateTime;
            while (businessDays > 0)
            {
                resultDate = resultDate.AddDays(1);
                if (resultDate.DayOfWeek != DayOfWeek.Saturday &&
                    resultDate.DayOfWeek != DayOfWeek.Sunday)
                    businessDays--;
            }
            return resultDate;
        }

Hope that helped you ;)