Calculating DateTime Difference or interval

Suppose that you have two date time values one is startdate and second is EndDate, and you want to calculate time interval between both dates ,in this situation we can use timespan object like this:

(According to MSDN: A TimeSpan object represents a time interval (duration of time or elapsed time) that is measured as a positive or negative number of days, hours, minutes, seconds, and fractions of a second. The TimeSpan structure can also be used to represent the time of day, but only if the time is unrelated to a particular date. Otherwise, the DateTime or DateTimeOffset structure should be used instead.)

Dim StartTime As DateTime = #6/12/2008 3:09:00 PM#

Dim EndTime As DateTime = #6/10/2008 12:04:00 PM#

Dim TimeDiff As TimeSpan = EndTime - StartTime

Dim Days As Integer = TimeDiff.Days 'calculate Value of Days Component

Dim Minutes As Integer = TimeDiff.Minutes 'calculate Value of Minutes Component

Dim Seconds As Integer = TimeDiff.Seconds 'calculate Value of Seconds Component

Dim TotalDays As Integer = TimeDiff.TotalDays 'calculate Value of Total Days

Dim TotalHours As Integer = TimeDiff.TotalHours 'calculate Value of Total Minutes

Dim TotalSeconds As Integer = TimeDiff.TotalSeconds 'calculate Value of Total Seconds

we can use subtrat method for calculating difference between two date like :

TimeDiff = EndTime.Subtract(StartTime)

Add a day, a month and a year to a Date

Dim FirstDate As Date

Dim SecondDate As Date

FirstDate = #2/28/2010#

'Add a day

SecondDate = FirstDate.AddDays(1)

'Add some months

SecondDate = FirstDate.AddMonths(6)

'Subtract a year

SecondDate = FirstDate.AddYears(-1)