Imports System.Net

Public Class MainWindow

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim i As Integer
        Try
            Dim ipE As IPHostEntry = Dns.GetHostEntry(TextBox1.Text)
            Dim IpA() As IPAddress = ipE.AddressList
            For i = 0 To IpA.GetUpperBound(0)
                Console.Write("IP Address {0}: {1} ", i, IpA(i).ToString)
                TextBox1.Text = IpA(i).ToString
            Next
        Catch
            TextBox1.Text = "Unable to locate host"
        End Try
    End Sub

End Class