Getting IP Address of the ACTIVE network card

[Paul Bromley]

How do I know which IP address is active??

I have created the following class and this works well, but the first
address it obtains on my machine is not the active one - in fact I do not
know what NIC it refers to the second one in the addresslist is the current
one (mIpAddr(1).ToS tring()). How can I test for the current active IP
address?? Many thanks in anticipation.

Many thanks

Paul Bromley
Imports System.Net
Public Class CGetLocalIPAddr ess
Dim sIpAddr As String
'Dim myLocalIP As New CGetLocalIPAddr ess
Public Sub New()
GetLocalIPAddre ss()
End Sub
Private Sub GetLocalIPAddre ss()
Dim ipEntry As IPHostEntry = Dns.GetHostByNa me(Environment. MachineName)
Dim mIpAddr As IPAddress() = ipEntry.Address List
Dim i As Integer
sIpAddr = mIpAddr(1).ToSt ring()
End Sub
Public Property LocalIPAddress( ) As String
Get
Return sIpAddr
End Get
Set(ByVal Value As String)
sIpAddr = Value
End Set
End Property
End Class

[Cor Ligthert [MVP]]

Paul,

In my idea are all those IP adresses active.
The IP address locates your computer on the network, it is not a device.

Cor

"Paul Bromley" <fl*******@dsl. pipex.comschree f in bericht
news:%2******** ********@TK2MSF TNGP06.phx.gbl. ..

How do I know which IP address is active??

I have created the following class and this works well, but the first
address it obtains on my machine is not the active one - in fact I do not
know what NIC it refers to the second one in the addresslist is the
current one (mIpAddr(1).ToS tring()). How can I test for the current active
IP address?? Many thanks in anticipation.

Many thanks

Paul Bromley
Imports System.Net
Public Class CGetLocalIPAddr ess
Dim sIpAddr As String
'Dim myLocalIP As New CGetLocalIPAddr ess
Public Sub New()
GetLocalIPAddre ss()
End Sub
Private Sub GetLocalIPAddre ss()
Dim ipEntry As IPHostEntry = Dns.GetHostByNa me(Environment. MachineName)
Dim mIpAddr As IPAddress() = ipEntry.Address List
Dim i As Integer
sIpAddr = mIpAddr(1).ToSt ring()
End Sub
Public Property LocalIPAddress( ) As String
Get
Return sIpAddr
End Get
Set(ByVal Value As String)
sIpAddr = Value
End Set
End Property
End Class

[Paul Bromley]

Hi Cor,

I only have one active IP address. I am not sure where the other one came
from.

Best wishes

Paul Bromley

"Cor Ligthert [MVP]" <no************ @planet.nlwrote in message
news:em******** ******@TK2MSFTN GP06.phx.gbl...

Paul,

In my idea are all those IP adresses active.
The IP address locates your computer on the network, it is not a device.

Cor

"Paul Bromley" <fl*******@dsl. pipex.comschree f in bericht
news:%2******** ********@TK2MSF TNGP06.phx.gbl. ..

>How do I know which IP address is active??

I have created the following class and this works well, but the first
address it obtains on my machine is not the active one - in fact I do not
know what NIC it refers to the second one in the addresslist is the
current one (mIpAddr(1).ToS tring()). How can I test for the current
active IP address?? Many thanks in anticipation.

Many thanks

Paul Bromley
Imports System.Net
Public Class CGetLocalIPAddr ess
Dim sIpAddr As String
'Dim myLocalIP As New CGetLocalIPAddr ess
Public Sub New()
GetLocalIPAddr ess()
End Sub
Private Sub GetLocalIPAddre ss()
Dim ipEntry As IPHostEntry = Dns.GetHostByNa me(Environment. MachineName)
Dim mIpAddr As IPAddress() = ipEntry.Address List
Dim i As Integer
sIpAddr = mIpAddr(1).ToSt ring()
End Sub
Public Property LocalIPAddress( ) As String
Get
Return sIpAddr
End Get
Set(ByVal Value As String)
sIpAddr = Value
End Set
End Property
End Class

[The Frog]

Hi Paul,

If you want to get the IP address of the active network card, or
possibly cards in a multi NIC machine, the easiest way to know you have
the right information is to get it from the registry directly. The code
below was written for VBA, but the principal is the same. It also takes
into account the possibility of inactive cards, and handles DHCP
assigned addresses as well as fixed.

i hope that this helps you. Sorry I havent the time to re-write it to
..Net.

Cheers

The Frog :)

------------------------------------------------------------------------------------

Function IPDiscover()
' This function retrieves the IP Address from the registry
' It gets it from the CurrentControlS et, so even when using DHCP
' it returns the correct IP Address

' Declare variables

Dim key
Dim cTempIPAddress As Variant
Dim cIPAddress
Dim cIPAddressKey
Set oSh = CreateObject("W Script.Shell")

cInterfaceskey =
"HKLM\SYSTEM\Cu rrentControlSet \Services\TCPIP \Parameters\Int erfaces\"
cNICSearch = "HKLM\SOFTWARE\ Microsoft\Windo ws
NT\CurrentVersi on\NetworkCards \1\ServiceName"
' First check which network card to use
cNicServiceName = oSh.RegRead(cNI CSearch)

' Now read the IP Address from that card
cIPAddressKey = cInterfaceskey + cNicServiceName + "\IPAddress "
cTempIPAddress = oSh.RegRead(cIP AddressKey)
cIPAddress = cTempIPAddress( 0)

If cIPAddress = "0.0.0.0" Then
cTempIPAddress = oSh.RegRead(cIn terfaceskey + cNicServiceName +
"\DhcpIPAddress ")
cIPAddress = ""
cIPAddress = cTempIPAddress
End If

'return the ip address to the function call
IPDiscover = cIPAddress
End Function

[Paul Bromley]

Many thanks for this. It should not be a problem for me to convert this to
vb.net. Many thanks

Paul Bromley

"The Frog" <an************ **@eu.effem.com wrote in message
news:11******** **************@ f16g2000cwb.goo glegroups.com.. .

Hi Paul,

If you want to get the IP address of the active network card, or
possibly cards in a multi NIC machine, the easiest way to know you have
the right information is to get it from the registry directly. The code
below was written for VBA, but the principal is the same. It also takes
into account the possibility of inactive cards, and handles DHCP
assigned addresses as well as fixed.

i hope that this helps you. Sorry I havent the time to re-write it to
.Net.

Cheers

The Frog :)

------------------------------------------------------------------------------------

Function IPDiscover()
' This function retrieves the IP Address from the registry
' It gets it from the CurrentControlS et, so even when using DHCP
' it returns the correct IP Address

' Declare variables

Dim key
Dim cTempIPAddress As Variant
Dim cIPAddress
Dim cIPAddressKey
Set oSh = CreateObject("W Script.Shell")

cInterfaceskey =
"HKLM\SYSTEM\Cu rrentControlSet \Services\TCPIP \Parameters\Int erfaces\"
cNICSearch = "HKLM\SOFTWARE\ Microsoft\Windo ws
NT\CurrentVersi on\NetworkCards \1\ServiceName"
' First check which network card to use
cNicServiceName = oSh.RegRead(cNI CSearch)

' Now read the IP Address from that card
cIPAddressKey = cInterfaceskey + cNicServiceName + "\IPAddress "
cTempIPAddress = oSh.RegRead(cIP AddressKey)
cIPAddress = cTempIPAddress( 0)

If cIPAddress = "0.0.0.0" Then
cTempIPAddress = oSh.RegRead(cIn terfaceskey + cNicServiceName +
"\DhcpIPAddress ")
cIPAddress = ""
cIPAddress = cTempIPAddress
End If

'return the ip address to the function call
IPDiscover = cIPAddress
End Function

[C-Services Holland b.v.]

What IP are you seeing that you're not expecting? 127.0.0.1? If it is,
that's the loopback address, it's always present.

Paul Bromley wrote:

How do I know which IP address is active??

I have created the following class and this works well, but the first
address it obtains on my machine is not the active one - in fact I do not
know what NIC it refers to the second one in the addresslist is the current
one (mIpAddr(1).ToS tring()). How can I test for the current active IP
address?? Many thanks in anticipation.

--
Rinze van Huizen
C-Services Holland b.v