How can I get local IP in .NET?

Question

I have the following vbscript code that returns the local IP address. It works great. I am trying to provide the same functionality in my winform .net app.

All the solutions I have come across involve using DNS. Any ideas on how to "port" this script for use in .net?

A different way to do this maybe?

Thanks!

Function GetIP()

 Dim ws : Set ws = CreateObject("WScript.Shell")
  Dim fso : Set fso = CreateObject("Scripting.FileSystemObject")
  Dim TmpFile : TmpFile = fso.GetSpecialFolder(2) & "/ip.txt"
  Dim ThisLine, IP
  If ws.Environment("SYSTEM")("OS") = "" Then
    ws.run "winipcfg /batch " & TmpFile, 0, True
  Else
    ws.run "%comspec% /c ipconfig > " & TmpFile, 0, True
  End If
  With fso.GetFile(TmpFile).OpenAsTextStream
    Do While NOT .AtEndOfStream
      ThisLine = .ReadLine
      If InStr(ThisLine, "Address") <> 0 Then IP = Mid(ThisLine, InStr(ThisLine, ":") + 2)
    Loop
    .Close
  End With

  If IP <> "" Then
    If Asc(Right(IP, 1)) = 13 Then IP = Left(IP, Len(IP) - 1)
  End If
  GetIP = IP
  fso.GetFile(TmpFile).Delete  
  Set fso = Nothing
  Set ws = Nothing
End Function

Answer 1

You can do this by querying the network interfaces, though this will include all local addresses so you may have to add a where clause to select the one you want if there are multiple interfaces (which there likely will be). It's certainly not a direct port of your script, but hopefully will be of some use:

var localAddress = 
    (from ni in NetworkInterface.GetAllNetworkInterfaces()
     where ni.NetworkInterfaceType != NetworkInterfaceType.Loopback
     let props = ni.GetIPProperties()
     from ipAddress in props.UnicastAddresses
     select ipAddress).FirstOrDefault();    

Note: If you only want IPv4 addresses, then you could alter the query to:

var localAddress = 
    (from ni in NetworkInterface.GetAllNetworkInterfaces()
     where ni.NetworkInterfaceType != NetworkInterfaceType.Loopback
     let props = ni.GetIPProperties()
     from ipAddress in props.UnicastAddresses
     where ipAddress.AddressFamily == AddressFamily.InterNetwork // IPv4
     select ipAddress).FirstOrDefault();