Check this out:
Imports System
Public Module Module1
Public Sub Main()
Dim firstdate As New Date(2015, 2, 1, 0, 0, 0)
Dim seconddate As New Date(2017, 1, 1, 0, 0, 0)
Dim timespan As TimeSpan = seconddate - firstdate
Dim interval As DateTime = DateTime.MinValue.AddDays(timespan.Days)
Console.WriteLine("{0} - {1} = {2} years", seconddate, firstdate, interval.Year - 1)
End Sub
End Module
Reference:
TimeSpan Structure (System)[
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