01.Private Sub Timer1_Tick(ByVal sender As System.Object, _
02. ByVal e As System.EventArgs) Handles Timer1.Tick
03.
04. counter = counter + 1
05. TextBox2.Text = counter
06. host = TextBox1.Text
07. port = TextBox2.Text
08.
09.
10.
11. Dim hostadd As System.Net.IPAddress = _
12. System.Net.Dns.GetHostEntry(host).AddressList(0)
13. Dim EPhost As New System.Net.IPEndPoint(hostadd, port)
14. Dim s As New System.Net.Sockets.Socket(_
15. System.Net.Sockets.AddressFamily.InterNetwork, _
16. System.Net.Sockets.SocketType.Stream, _
17. System.Net.Sockets.ProtocolType.Tcp)
18. Try
19. s.Connect(EPhost)
20. Catch
21. End Try
22. If Not s.Connected Then
23. ListBox1.Items.Add("Port " + port.ToString + " is not open")
24. Else
25. ListBox1.Items.Add("Port " + port.ToString + " is open")
26. ListBox2.Items.Add(port.ToString)
27. End If
28. Label3.Text = "Open Ports: " + ListBox2.Items.Count.ToString
29.End Sub
