Get IP Addresses of 6 devices using MAC addresses using VB.NET - vb.net

Question

How do I modify my code to populate a listbox of IP addresses if I know 6 devices MAC addresses?
I am using VB.net to show me my current IP and MAC address but I want to change it to add to a ListBox to show 6 devices on the same network using their MAC addresses. Since we cannot modify the DHCP server, we just want a simple way to show each device's IP address using their known Mac addresses. I will add the MAC addresses in code. but Just want to have the listbox populate on startup of the app.
Existing Code:
Imports System.Net
Imports System.Runtime.InteropServices
Imports System.ComponentModel
Imports System.IO
Imports System.Net.NetworkInformation
Public Class Form1
Private Sub Form1_MouseClick(sender As Object, e As MouseEventArgs) Handles Me.MouseClick
Dim mac As String
mac = GetMacAddress()
Label1.Text = mac
End Sub
Function GetMacAddress()
Dim nics() As NetworkInterface = NetworkInterface.GetAllNetworkInterfaces()
Return nics(0).GetPhysicalAddress.ToString
End Function
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Me.Close()
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
GetIPv4Address()
End Sub
Private Function GetIPv4Address() As String
GetIPv4Address = String.Empty
Dim strHostName As String = System.Net.Dns.GetHostName()
Dim iphe As System.Net.IPHostEntry = System.Net.Dns.GetHostEntry(strHostName)
For Each ipheal As System.Net.IPAddress In iphe.AddressList
If ipheal.AddressFamily = System.Net.Sockets.AddressFamily.InterNetwork Then
GetIPv4Address = ipheal.ToString()
Label2.Text = "IP Address: " & ipheal.ToString
End If
Next
End Function
End Class
Thanks in advance!

Answer 1

Updated Answer - After some more digging, I found untweaked version of the code below here and tweaked it a bit.
What you end up with is a list of IpInfo structures. Each of these objects has the self-explanatory properties of IpAddress, MacAddress and HostName. You can iterate through the list and IP addresses the matching mac addresses to your listbox.
You may need to tweak the Thread.Sleep interval to make sure that you get all the results, but I hope this new answer sorts you out.
If it does, I would suggest removing the comments about the code not working so that they don't confuse others looking at this answer.
Imports System.Net
Imports System.Net.NetworkInformation
Imports System.Net.Sockets
Public Class Form1
Structure IpInfo
Dim IpAddress As String
Dim HostName As String
Dim MacAddress As String
End Structure
Dim connectedIPAddresses As New List(Of IpInfo)
Private Shared Function NetworkGateway() As String
Dim ip As String = Nothing
For Each f As NetworkInterface In NetworkInterface.GetAllNetworkInterfaces()
If f.OperationalStatus = OperationalStatus.Up Then
For Each d As GatewayIPAddressInformation In f.GetIPProperties().GatewayAddresses
ip = d.Address.ToString()
Next
End If
Next
Return ip
End Function
Public Sub Ping_all()
Dim gate_ip As String = NetworkGateway()
Dim array As String() = gate_ip.Split("."c)
For i As Integer = 2 To 255
Dim ping_var As String = array(0) & "." & array(1) & "." & array(2) & "." & i.ToString
Ping(ping_var, 1, 1000)
Next
Task.WhenAll(taskList)
End Sub
Dim taskList As New List(Of Task)
Public Sub Ping(ByVal host As String, ByVal attempts As Integer, ByVal timeout As Integer)
For i As Integer = 0 To attempts - 1
taskList.Add(Task.Run(Sub()
Try
Dim ping As System.Net.NetworkInformation.Ping = New System.Net.NetworkInformation.Ping()
AddHandler ping.PingCompleted, AddressOf PingCompleted
ping.SendAsync(host, timeout, host)
Catch
End Try
End Sub))
Next
End Sub
Private Sub PingCompleted(ByVal sender As Object, ByVal e As PingCompletedEventArgs)
Dim ip As String = CStr(e.UserState)
If e.Reply IsNot Nothing AndAlso e.Reply.Status = IPStatus.Success Then
Dim hostname As String = GetHostName(ip)
Dim macaddres As String = GetMacAddress(ip)
Dim newIpAddress As IpInfo
newIpAddress.IpAddress = ip
newIpAddress.MacAddress = macaddres
newIpAddress.HostName = hostname
connectedIPAddresses.Add(newIpAddress)
Else
End If
End Sub
Public Function GetHostName(ByVal ipAddress As String) As String
Try
Dim entry As IPHostEntry = Dns.GetHostEntry(ipAddress)
If entry IsNot Nothing Then
Return entry.HostName
End If
Catch __unusedSocketException1__ As SocketException
End Try
Return Nothing
End Function
Public Function GetMacAddress(ByVal ipAddress As String) As String
Dim macAddress As String = String.Empty
Dim Process As System.Diagnostics.Process = New System.Diagnostics.Process()
Process.StartInfo.FileName = "arp"
Process.StartInfo.Arguments = "-a " & ipAddress
Process.StartInfo.UseShellExecute = False
Process.StartInfo.RedirectStandardOutput = True
Process.StartInfo.CreateNoWindow = True
Process.Start()
Dim strOutput As String = Process.StandardOutput.ReadToEnd()
Dim substrings As String() = strOutput.Split("-"c)
If substrings.Length >= 8 Then
macAddress = substrings(3).Substring(Math.Max(0, substrings(3).Length - 2)) & "-" & substrings(4) & "-" & substrings(5) & "-" & substrings(6) & "-" & substrings(7) & "-" + substrings(8).Substring(0, 2)
Return macAddress
Else
Return "OWN Machine"
End If
End Function
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Ping_all()
Threading.Thread.Sleep(10000)
For Each ip As IpInfo In connectedIPAddresses
ListBox1.Items.Add(ip.IpAddress)
Next
End Sub