VB.Net Tutorial/Class Module/Function Parameters

Argument Order

Imports System
Public Module Test
    Public Function Add(ByVal Num1 As Integer, ByVal Num2 As Double) As Double
        Return Num1 + Num2
    End Function
    
    Public Function Add(ByVal Num2 As Double, ByVal Num1 As Integer) As Double
        Return Num1 - Num2
    End Function
    
    Sub Main()
    
        Dim Num3 As Double = Add(2, 4.2)
        Dim Num4 As Double = Add(4.2 , 2)
    
        Console.WriteLine("The first Add Method " & Num3)
        Console.WriteLine("The Second Add Method " & Num4)
    
    End Sub
End Module

The first Add Method 6.2
The Second Add Method -2.2

Optional parameters

Module Module1
    Sub Main()
        ShowMessage()
    End Sub
    Sub ShowMessage(Optional ByVal strText As String = "Hello there!")
        System.Console.WriteLine(strText)
    End Sub
End Module

Hello there!