DateInterval.Constructor(years As Integer = 0, months As Integer = 0, days As Integer = 0, hours As Integer = 0, minutes As Integer = 0, seconds As Integer = 0, nanoseconds As Integer = 0)

From Xojo Documentation

Constructor
DateInterval.Constructor(years As Integer = 0, months As Integer = 0, days As Integer = 0, hours As Integer = 0, minutes As Integer = 0, seconds As Integer = 0, nanoseconds As Integer = 0)

Specifies an interval using the various properties to create a date and time.

Sample Code

Creates a date that is two months from today and two months before today:

Var di As New DateInterval(0, 2) // 0 years, 2 months
// Get date two months from today
Var d1 As Date = Date.Now + di
// Get date two months before today
Var d2 As Date = Date.Now - di