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Xamarin forms GET DNS server from WIFI connection

I am using xamarin forms and i have one problem,
i am trying to get the DNS server Adresse from WIFI, and a im using below code :
NetworkInterface[] networkInterfaces = NetworkInterface.GetAllNetworkInterfaces();
foreach (NetworkInterface networkInterface in networkInterfaces)
{
if (networkInterface.OperationalStatus == OperationalStatus.Up)
{
IPInterfaceProperties ipProperties = networkInterface.GetIPProperties();
IPAddressCollection dnsAddresses = ipProperties.DnsAddresses;
foreach (IPAddress dnsAdress in dnsAddresses)
{
Debug.WriteLine(dnsAdress);
}
}
}
The problem is when i use this code on Microsoft Emulator "UWP" everything work fine see picture bellow using UWP device
but nothing work when i use my android mobile see picture bellow
using android device
NB: all devices are connect on the same wifi

I had done a simple to test your code and got the same null. And then I read the IPInterfaceProperties.DnsAddresses Property document, it seems that it doesn't support the xamarin.android.
You can check the it:https://learn.microsoft.com/en-us/dotnet/api/system.net.networkinformation.ipinterfaceproperties.dnsaddresses?view=net-6.0
In addition, I also search this but can not find any solution. So I try to use the android native method to get the dns address with the following code. So you can try to use the dependency service to get the dns address for android.
ConnectivityManager cm = (ConnectivityManager)GetSystemService(ConnectivityService);
//NetworkInfo has been deprecated, but I can not find the new api to to this
NetworkInfo activeNetworkInfo = cm.ActiveNetworkInfo;
foreach (Network network in cm.GetAllNetworks())
{
NetworkInfo networkInfo = cm.GetNetworkInfo(network);
if (networkInfo.GetType() == activeNetworkInfo.GetType())
{
LinkProperties lp = cm.GetLinkProperties(network);
foreach (InetAddress addr in lp.DnsServers)
{
var a = addr.GetAddress();
}
}
}

Find ip of certain windows phone device in your local network

I'm trying to build C# app (desktop,windows, it doesn't really matter for now), with which I would like to connect to my windows phone, using sockets, to transfer some data... I know how this can be achieved,.
When connecting through sockets I don't want to manually enter windows phone device's IP address. So I want to know if it is possible to send some HTTP request from Windows phone app with some message, and fetch that message on computer, to be sure which IP is windows phone's IP?
In other words how to know which IP address belongs to Windows phone's IP address from Bunch of Ip addresses of devices on network?

Fallow this Link from Here
Add NameSpace :
using Windows.Networking;
public static string FindIPAddress()
{
List<string> ipAddresses = new List<string>();
var hostnames = NetworkInformation.GetHostNames();
foreach (var hn in hostnames)
{
//IanaInterfaceType == 71 => Wifi
//IanaInterfaceType == 6 => Ethernet (Emulator)
if (hn.IPInformation != null &&
(hn.IPInformation.NetworkAdapter.IanaInterfaceType == 71
|| hn.IPInformation.NetworkAdapter.IanaInterfaceType == 6))
{
string ipAddress = hn.DisplayName;
ipAddresses.Add(ipAddress);
}
}
if (ipAddresses.Count < 1)
{
return null;
}
else if (ipAddresses.Count == 1)
{
return ipAddresses[0];
}
else
{
//if multiple suitable address were found use the last one
//(regularly the external interface of an emulated device)
return ipAddresses[ipAddresses.Count - 1];
}
}
Edit:
If I am wrong You want to get particular Windows Phone IP address from bunch of IP addresses. AFAIK you can't get like this. But I suggest you to Append some string when getting IP of Windows Phone like below which will vary from other Ip addresses by looking it self.
string IPadd = FindIPAddress();
string WPIPadd = IPadd + " - Windows phone "
MessageDialog.show(WPIPadd);
If you find any thing new apart from this Let us know. Thanks

Get the properties of the current network connection

How do you determine or examine the connection profile of the current network connection (if any)?
Specifically, I need to determine if the current connection is to a private or public network, and from there determine whether network discovery is turned on or off.
It seems like this information is readily available in a Windows Store app via the Windows.Networking.Connectivity.NetworkInformation.GetConnectionProfiles() or NetworkInformation.GetInternetConnectionProfile() functions, but this is a standard desktop app that must run on Win 7 and Server 2008 as well as Win 8 and Server 2012.
Enumerating the NICs on a machine is not a problem, but this doesn't solve my issue - I need to get the properties of the connection, not the physical device.
Is there an inbuilt way to do this with the .Net framework? Alternatively can it be done with WMI? Or as a crude alternative, can it be done by invoking the netsh command (although this seems to depend on the dot3svc and/or wlansvc services to be running)?

You can use Network List Manager API for that purpose, to use it from C# import Network List Manager Type Library.
Then you must enumerate all connected networks, because there can be more than one, for example right now I am connected to internet and VPN. Then for all connected networks call GetCategory() API, it returns NLM_NETWORK_CATEGORY (private, public or domain).
Here is the sample code (add using NETWORKLIST in use clauses) :
var manager = new NetworkListManager();
var connectedNetworks = manager.GetNetworks(NLM_ENUM_NETWORK.NLM_ENUM_NETWORK_CONNECTED).Cast<INetwork>();
foreach (var network in connectedNetworks)
{
Console.Write(network.GetName() + " ");
var cat = network.GetCategory();
if (cat == NLM_NETWORK_CATEGORY.NLM_NETWORK_CATEGORY_PRIVATE)
Console.WriteLine("[PRIVATE]");
else if (cat == NLM_NETWORK_CATEGORY.NLM_NETWORK_CATEGORY_PUBLIC)
Console.WriteLine("[PUBLIC]");
else if (cat == NLM_NETWORK_CATEGORY.NLM_NETWORK_CATEGORY_DOMAIN_AUTHENTICATED)
Console.WriteLine("[DOMAIN]");
}
Console.ReadKey();
For this to work one must add reference to COM Network List 1.0 Type Library, like this:
For Network Discovery you have to use Firewall API and reference COM library NetFwTypeLib and get INetFwProfile for active profile, then in services there are File sharing, Network Discovery and Remote Desktop services, and there is a bool flag if these are Enabled. Here is the example code : (just to warn you I didn't use below code in production I was just exploring this API)
Type objectType = Type.GetTypeFromCLSID(new Guid("{304CE942-6E39-40D8-943A-B913C40C9CD4}"));
var man = Activator.CreateInstance(objectType) as INetFwMgr;
/// get current profile
INetFwProfile prof = man.LocalPolicy.CurrentProfile;
Console.WriteLine("Current profile ");
ShowProfileServices(prof);
And the method that shows profile services.
private static void ShowProfileServices(INetFwProfile prof)
{
var services = prof.Services.Cast<INetFwService>();
var sharing = services.FirstOrDefault(sc => sc.Name == "File and Printer Sharing");
if (sharing != null)
Console.WriteLine(sharing.Name + " Enabled : " + sharing.Enabled.ToString());
else
Console.WriteLine("No sharing service !");
var discovery = services.FirstOrDefault(sc => sc.Name == "Network Discovery");
if (discovery != null)
Console.WriteLine(discovery.Name + " Enabled : " + discovery.Enabled.ToString());
else
Console.WriteLine("No network discovery service !");
var remoteDesktop = services.FirstOrDefault(sc => sc.Name == "Remote Desktop");
if (remoteDesktop != null)
Console.WriteLine(remoteDesktop.Name + " Enabled : " + remoteDesktop.Enabled.ToString());
else
Console.WriteLine("No remote desktop service !");
}

I know this question is super old, but I faced this problem recently - how to get Network Category (private or public) in C# using Windows.Network.Connectivity from Windows Runtime API.
There is almost everything related to networking but I could not find the Network Category.
The solution is NetworkTypes enum.
https://learn.microsoft.com/en-us/uwp/api/windows.networking.connectivity.networktypes?view=winrt-22000
Simply check if returned types has flag PrivateNetwork. If yes - then is't private, if not - it's public.
Example code below:
var adapters = NetworkInterface.GetAllNetworkInterfaces();
var upNetworkInterfaces = adapters.Where(x =>
x.Supports(NetworkInterfaceComponent.IPv4) &&
x.NetworkInterfaceType is NetworkInterfaceType.Ethernet or NetworkInterfaceType.Wireless80211);
foreach (var adapter in upNetworkInterfaces)
{
var hostname = NetworkInformation.GetHostNames()
.FirstOrDefault(x =>
x.IPInformation != null &&
string.Equals(x.IPInformation.NetworkAdapter.NetworkAdapterId.ToString(),
adapter.Id.Replace("{", string.Empty).Replace("}", string.Empty),
StringComparison.InvariantCultureIgnoreCase));
if (hostname is not null)
{
var networkTypes = hostname.IPInformation.NetworkAdapter.NetworkItem.GetNetworkTypes();
var privateNetwork = networkTypes.HasFlag(NetworkTypes.PrivateNetwork)
? NetworkAccessibilityLevel.Private
: NetworkAccessibilityLevel.Public;
}
}

How to get network adapter index?

From code I want to force a Windows machine to use a specific network adapter for all connections to a specific IP address.
I plan to do so by using the ROUTE ADD command line tool, but this requires that I know in advance the network adapters' index number (as it must be given to the ROUTE ADD command).
QUESTION: How can I programmatically retrieve a network adapter's index, given I know its name?
I'm aware that ROUTE PRINT shows me the information I need (the index numbers of all network adapters present), but there must be a way to get that information programmatically too (C#)?
Note, that I don't like parsing the text output from ROUTE PRINT, as the text format may change with different Windows versions.

You can obtain the interface index of your network adapter
by using the .Net NetworkInterface (and related) classes.
Here is a code example:
static void PrintInterfaceIndex(string adapterName)
{
NetworkInterface[] nics = NetworkInterface.GetAllNetworkInterfaces();
IPGlobalProperties properties = IPGlobalProperties.GetIPGlobalProperties();
Console.WriteLine("IPv4 interface information for {0}.{1}",
properties.HostName, properties.DomainName);
foreach (NetworkInterface adapter in nics)
{
if (adapter.Supports(NetworkInterfaceComponent.IPv4) == false)
{
continue;
}
if (!adapter.Description.Equals(adapterName, StringComparison.OrdinalIgnoreCase))
{
continue;
}
Console.WriteLine(adapter.Description);
IPInterfaceProperties adapterProperties = adapter.GetIPProperties();
IPv4InterfaceProperties p = adapterProperties.GetIPv4Properties();
if (p == null)
{
Console.WriteLine("No information is available for this interface.");
continue;
}
Console.WriteLine(" Index : {0}", p.Index);
}
}
Then just call this function with the name of your network adapter:
PrintInterfaceIndex("your network adapter name");
You can also obtain the InterfaceIndex of your network adapter
by using the Win32_NetworkAdapter WMI class. The Win32_NetworkAdapter class
contains a property called InterfaceIndex.
So, to retrieve the InterfaceIndex for a network adapter with a given
name, use the following code:
ManagementScope scope = new ManagementScope("\\\\.\\ROOT\\cimv2");
ObjectQuery query = new ObjectQuery("SELECT * FROM Win32_NetworkAdapter WHERE Description='<Your Network Adapter name goes here>'");
using (ManagementObjectSearcher searcher = new ManagementObjectSearcher(scope, query))
{
using (ManagementObjectCollection queryCollection = searcher.Get())
{
foreach (ManagementObject mo in queryCollection)
{
Console.WriteLine("InterfaceIndex : {0}, name {1}", mo["InterfaceIndex"], mo["Description"]);
}
}
}
If you do not want to use WMI you could also use the Win32 API function
GetAdaptersInfo in combination with the IP_ADAPTER_INFO struct.
You will find an example here pinvoke.net.

have you looked into using C#'s system.net.networkinformation interface?
http://msdn.microsoft.com/en-us/library/system.net.networkinformation.networkinterface.getallnetworkinterfaces.aspx
I'm not familiar with ROUTE ADD, but you can theoretically marry up information from one with the other.

Query Local IP Address

I have the need to know my actual local IP address (i.e. not the loopback address) from a Windows 8 WinRT/Metro app. There are several reasons I need this. The simplest is that in the UI of the app I'd like to show some text like "Your local network IP address is: [IP queried from code]".
We also use the address for some additional network comms. Those comms are perfectly valid because it all works if I look at the IP address in the Control Panel, then hard-code it into the app. Asking the user in a dialog to go look at the address and manually enter it is something I really, really want to avoid.
I would think it wouldn't be a complex task to get the address programmatically, but my search engine and StackOverflow skills are coming up empty.
At this point I'm starting to consider doing a UDP broadcast/listen loop to hear my own request and extract the address from that, but that really seems like a hackey kludge. Is there an API somewhere in the new WinRT stuff that will get me there?
Note that I said "WinRT app. That means the typical mechanisms like Dns.GetHostEntry or NetworkInterface.GetAllInterfaces() aren't going to work.

After much digging, I found the information you need using NetworkInformation and HostName.
NetworkInformation.GetInternetConnectionProfile retrieves the connection profile associated with the internet connection currently used by the local machine.
NetworkInformation.GetHostNames retrieves a list of host names. It's not obvious but this includes IPv4 and IPv6 addresses as strings.
Using this information we can get the IP address of the network adapter connected to the internet like this:
public string CurrentIPAddress()
{
var icp = NetworkInformation.GetInternetConnectionProfile();
if (icp != null && icp.NetworkAdapter != null)
{
var hostname =
NetworkInformation.GetHostNames()
.SingleOrDefault(
hn =>
hn.IPInformation != null && hn.IPInformation.NetworkAdapter != null
&& hn.IPInformation.NetworkAdapter.NetworkAdapterId
== icp.NetworkAdapter.NetworkAdapterId);
if (hostname != null)
{
// the ip address
return hostname.CanonicalName;
}
}
return string.Empty;
}
Note that HostName has properties CanonicalName, DisplayName and RawName, but they all seem to return the same string.
We can also get addresses for multiple adapters with code similar to this:
private IEnumerable<string> GetCurrentIpAddresses()
{
var profiles = NetworkInformation.GetConnectionProfiles().ToList();
// the Internet connection profile doesn't seem to be in the above list
profiles.Add(NetworkInformation.GetInternetConnectionProfile());
IEnumerable<HostName> hostnames =
NetworkInformation.GetHostNames().Where(h =>
h.IPInformation != null &&
h.IPInformation.NetworkAdapter != null).ToList();
return (from h in hostnames
from p in profiles
where h.IPInformation.NetworkAdapter.NetworkAdapterId ==
p.NetworkAdapter.NetworkAdapterId
select string.Format("{0}, {1}", p.ProfileName, h.CanonicalName)).ToList();
}

About the accepted answer, you just need this:
HostName localHostName = NetworkInformation.GetHostNames().FirstOrDefault(h =>
h.IPInformation != null &&
h.IPInformation.NetworkAdapter != null);
You can get the local IP Address this way:
string ipAddress = localHostName.RawName; //XXX.XXX.XXX.XXX
Namespaces used:
using System.Linq;
using Windows.Networking;
using Windows.Networking.Connectivity;