Imports System
Imports System.Net
Module Module1
Function CheckIpAddress(s As String) As String
Dim ip As IPAddress = Nothing
If IPAddress.TryParse(s, ip) Then
If ip.AddressFamily = Sockets.AddressFamily.InterNetwork Then
Return "IPv4"
ElseIf ip.AddressFamily = Sockets.AddressFamily.InterNetworkV6 Then
Return "IPv6"
End If
End If
Return "Invalid"
End Function
Sub Main()
Console.WriteLine(CheckIpAddress("112.128.1.2"))
Console.WriteLine(CheckIpAddress("2001:0dc7:85b2:0000:0000:6d3e:0380:8651"))
Console.WriteLine(CheckIpAddress("999.999.999.999"))
Console.WriteLine(CheckIpAddress("abc"))
End Sub
End Module
' run:
'
' IPv4
' IPv6
' Invalid
' Invalid
'
