Question: how to calculate date in vb.net?
Answer: Dim newDate As New DateTime(2000, 5, 1) Here newDate represents year as 2000 and month as May and date as 1 . ... 
Dim diff As System.TimeSpan = secondDate.Subtract(firstDate) You can also find the difference between two dates using the following method.
Dim diff2 As String = (secondDate - firstDate).TotalDays.ToString()