Imports System
Module Program
''' <summary>
''' Returns the number of complete months between two dates.
''' </summary>
''' <param name="startdate">Start date.</param>
''' <param name="enddate">End date.</param>
''' <returns>Number of complete months.</returns>
Function GetMonthsBetween(startdate As Date, enddate As Date) As Integer
' Calculate the raw month difference.
Dim months As Integer =
((enddate.Year - startdate.Year) * 12) +
(enddate.Month - startdate.Month)
' If the end day is before the start day,
' the last month has not been completed.
If enddate.Day < startdate.Day Then
months -= 1
End If
Return months
End Function
Sub Main()
' Start date: 2026/1/15
Dim startdate As New Date(2026, 1, 15)
' End date: 2027/7/20
Dim enddate As New Date(2027, 7, 20)
Dim months As Integer = GetMonthsBetween(startdate, enddate)
Console.WriteLine($"Months between dates: {months}")
End Sub
End Module
' run:
'
' Months between dates: 18
'
