I'm working with a Xamarin.Forms cross-platform app. Now, I need to obtain the device home Ip (I mean the static one). Which is the simplest way to get the IPv4 address of the device in Xamarin.Forms?
You can use Dns.GetHostAddresses which is under using System.Net
Call this function
var ip = GetLocalAddress();
GetLocalAddress:
private string GetLocalAddress()
{
var IpAddress = Dns.GetHostAddresses(Dns.GetHostName()).FirstOrDefault();
if (IpAddress != null)
return IpAddress.ToString();
return "Could not locate IP Address";
}
You can use DependencyService to get Ip address, then following code is Android project. For other Platform, you can take a look:
class IPAddressManager : IIPAddressManager
{
public string GetIPAddress()
{
IPAddress[] addresses = Dns.GetHostAddresses(Dns.GetHostName());
if (addresses?[0] != null)
{
return addresses[0].ToString();
}
else
{
return null;
}
}
}
https://theconfuzedsourcecode.wordpress.com/2015/05/16/how-to-easily-get-device-ip-address-in-xamarin-forms-using-dependencyservice/
Is it possible to use the IUserIDProvider instead of ConnectionID when working with Groups? I have already found an answer here, but that concerns the SignalR 1.0 version. I wonder, whether things have changed in 2.0.
So far, I was using the conventional
Groups.Add(Context.ConnectionId, "groupName");
However, it was difficult to keep track of the connected users when their connectionID was changed (the client is a Xamarin Android app and somehow, reconnection always resulted in creation of a new ConnectionID). Thus, when the client is connecting, I have added a header:
public async Task<bool> Login(int waitMilis, string name)
{
var cts = new CancellationTokenSource();
try
{
cts.CancelAfter(waitMilis);
_connection.Headers.Add("userName", name);
await _connection.Start();
return true;
}
catch(Exception ex)
{
CallFailure(ex);
return false;
}
}
And on server side, implemented the IUserIdProvider:
public class MyUserProvider : IUserIdProvider
{
public string GetUserId(IRequest request)
{
if (request == null)
throw new ArgumentNullException("request");
else if (request.Headers != null && request.Headers["userName"] != null)
return request.Headers["userName"].ToString();
else return null;
}
}
Now, I would like to do something like
Groups.Add("userName", "groupName");
but the Add method does not have an overload for IUserIdProvider. So, is there a possibility to combine the IUserIdProvider and working with Groups, or am I stuck to creating a ConcurrentDictionary and then calling this?
foreach(User user in group.Users)
{
Clients.User(user.Name).SendMessage(message,
group.LastUpdateIndex
);
}
It ruins the whole beauty and simplicity of the SignalR code :-/
Unfortunately, there isn't currently a method like Groups.Add("userName", "groupName"); in SignalR.
I suggest adding users to their appropriate group(s) in OnConnected:
public class MyHub : Hub
{
public override async Task OnConnected()
{
var userName = MyUserHelper.GetUserId(Context.Request);
foreach (var groupName in GroupManager.GetJoinedGroups(userName))
{
await Groups.Add(Context.ConnectionId, groupName);
}
}
// ...
}
If you need to add an already connected user to a group, then you will likely need to send a message to the user using something like Clients.User(userName).joinGroup(groupName). Each client with userName could then call the appropriate hub method to join groupName.
I’m trying to build a chat apps whereby users id are represented by their auto generated signalR connection id. On page refresh, the connection id changes when a new connection is instantiated. Is there a way to persist the state of the connection id of a user until the browser session is ended (i.e until he ends his session on client).
Any guide or documentation? It really would help.
i am new in signalr. so trying to know many things searching Google. from this url i got a similar snippet http://kevgriffin.com/maintaining-signalr-connectionids-across-page-instances/
they are saying it is possible. the problem is signalr often create a new connection id if we referesh the page. i want to prevent this but how.......
this code snippet.
public class MyConnectionFactory : IConnectionIdFactory
{
public string CreateConnectionId(IRequest request)
{
if (request.Cookies["srconnectionid"] != null)
{
return request.Cookies["srconnectionid"];
}
return Guid.NewGuid().ToString();
}
}
$.connection.hub.start().done(function () {
alert("Connected!");
var myClientId = $.connection.hub.id;
setCookie("srconnectionid", myClientId);
});
function setCookie(cName, value, exdays) {
var exdate = new Date();
exdate.setDate(exdate.getDate() + exdays);
var c_value = escape(value) + ((exdays == null) ? "" : "; expires=" + exdate.toUTCString());
document.cookie = cName + "=" + c_value;
}
my doubt is does it work in all signalr version? if not then how to handle it in new version specially for not generate a new connection id if page gets refreshed. looking for suggestion.
if we work with Persistent connection class instead of hub then what happen.....in this case connection id will persist if we refresh the page at client side? please guide.
thanks
SignalR allows you to send messages to a user via their IPrincipal.Identity.Name. Just use Clients.User(userName) instead of Clients.Client(connectionId).
If you for some reason cannot address a user using their IPrincipal.Identity.Name you could create your own IUserIdProvider. This is the replacement for IConnectionIdFactory which no longer exists in SignalR >= 1.0.0.
The equivalent IUserIdProvider would look like this:
public class MyConnectionFactory : IUserIdProvider
{
public string GetUserId(IRequest request)
{
if (request.Cookies["srconnectionid"] != null)
{
return request.Cookies["srconnectionid"];
}
return Guid.NewGuid().ToString();
}
}
public class Startup
{
public void Configuration(IAppBuilder app)
{
var idProvider = new MyConnectionFactory();
GlobalHost.DependencyResolver.Register(typeof(IUserIdProvider), () => idProvider);
app.MapSignalR();
}
}
public class MyHub : Hub
{
public Task Send(string userName, string message)
{
return Clients.User(userName).receive(message);
}
}
It would be really trivial to spoof a user given this MyConnectionFactory. You could make it more secure by using an HMAC.
Ideally you would just use the default IUserIdProvider which retrieves the user ID from IRequest.User.Identity.Name.
The user id provider doesn't work, because the connection id doesn't come from it. I implemented a solution (https://weblogs.asp.net/ricardoperes/persisting-signalr-connections-across-page-reloads) that uses a pseudo-session id stored in session storage. Every SignalR connection id is then mapped to this pseudo-session id.
On server side I have
public class Global : System.Web.HttpApplication
{
private static List<UserInfo> _Users;
public static List<UserInfo> Users
{
get { return Global._Users; }
set
{
lock (_Users)
{
Global._Users = value;
}
}
}
...
public class RawHub : PersistentConnection
{
protected override Task OnConnected(IRequest request, string connectionId)
{
var UserID = request.QueryString.Where(t => t.Key == "U");
if (!string.IsNullOrEmpty(UserID.First().Value))
{
var ui = new Guid(UserID.First().Value);
var user = Global.Users.FirstOrDefault(x => x.USERID == ui);
if (user == null)
{
var us = new UserInfo();
us.USERID = ui;
us.ConnectionId = connectionId;
Global.Users.Add(us);
}
else
{
user.ConnectionId=connectionId;
}
return Connection.Send(user.ConnectionId,"Good To Go");
}
}
I want to tryout send users their specific infos user by user with Send ...
bu I have to clean up Global.Users when they are disconnected.
Q: Is that possible to catch pings ? from js client or must i have to ping to client to detect live or not ?
What is the best approach
thnks
May br you can send custom i am alive messages from js client. Becouse some times ping doesnot come from client as expected. Usually when network is busy this happens...
good luck
Not sure what exactly is the problem here but you can simply listen for messages/pings in OnReceived
asp.net/signalr
We have Request.UserHostAddress to get the IP address in ASP.NET, but this is usually the user's ISP's IP address, not exactly the user's machine IP address who for example clicked a link. How can I get the real IP Address?
For example, in a Stack Overflow user profile it is: "Last account activity: 4 hours ago from 86.123.127.8", but my machine IP address is a bit different. How does Stack Overflow get this address?
In some web systems there is an IP address check for some purposes. For example, with a certain IP address, for every 24 hours can the user just have only 5 clicks on download links? This IP address should be unique, not for an ISP that has a huge range of clients or Internet users.
Did I understand well?
Often you will want to know the IP address of someone visiting your website. While ASP.NET has several ways to do this one of the best ways we've seen is by using the "HTTP_X_FORWARDED_FOR" of the ServerVariables collection.
Here's why...
Sometimes your visitors are behind either a proxy server or a router and the standard Request.UserHostAddress only captures the IP address of the proxy server or router. When this is the case the user's IP address is then stored in the server variable ("HTTP_X_FORWARDED_FOR").
So what we want to do is first check "HTTP_X_FORWARDED_FOR" and if that is empty we then simply return ServerVariables("REMOTE_ADDR").
While this method is not foolproof, it can lead to better results. Below is the ASP.NET code in VB.NET, taken from James Crowley's blog post "Gotcha: HTTP_X_FORWARDED_FOR returns multiple IP addresses"
C#
protected string GetIPAddress()
{
System.Web.HttpContext context = System.Web.HttpContext.Current;
string ipAddress = context.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ipAddress))
{
string[] addresses = ipAddress.Split(',');
if (addresses.Length != 0)
{
return addresses[0];
}
}
return context.Request.ServerVariables["REMOTE_ADDR"];
}
VB.NET
Public Shared Function GetIPAddress() As String
Dim context As System.Web.HttpContext = System.Web.HttpContext.Current
Dim sIPAddress As String = context.Request.ServerVariables("HTTP_X_FORWARDED_FOR")
If String.IsNullOrEmpty(sIPAddress) Then
Return context.Request.ServerVariables("REMOTE_ADDR")
Else
Dim ipArray As String() = sIPAddress.Split(New [Char]() {","c})
Return ipArray(0)
End If
End Function
As others have said you can't do what you are asking. If you describe the problem you are trying to solve maybe someone can help?
E.g.
are you trying to uniquely identify your users?
Could you use a cookie, or the session ID perhaps instead of the IP address?
Edit The address you see on the server shouldn't be the ISP's address, as you say that would be a huge range. The address for a home user on broadband will be the address at their router, so every device inside the house will appear on the outside to be the same, but the router uses NAT to ensure that traffic is routed to each device correctly. For users accessing from an office environment the address may well be the same for all users. Sites that use IP address for ID run the risk of getting it very wrong - the examples you give are good ones and they often fail. For example my office is in the UK, the breakout point (where I "appear" to be on the internet) is in another country where our main IT facility is, so from my office my IP address appears to be not in the UK. For this reason I can't access UK only web content, such as the BBC iPlayer). At any given time there would be hundreds, or even thousands, of people at my company who appear to be accessing the web from the same IP address.
When you are writing server code you can never be sure what the IP address you see is referring to. Some users like it this way. Some people deliberately use a proxy or VPN to further confound you.
When you say your machine address is different to the IP address shown on StackOverflow, how are you finding out your machine address? If you are just looking locally using ipconfig or something like that I would expect it to be different for the reasons I outlined above. If you want to double check what the outside world thinks have a look at whatismyipaddress.com/.
This Wikipedia link on NAT will provide you some background on this.
UPDATE:
Thanks to Bruno Lopes. If several ip addresses could come then need to use this method:
private string GetUserIP()
{
string ipList = Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ipList))
{
return ipList.Split(',')[0];
}
return Request.ServerVariables["REMOTE_ADDR"];
}
If is c# see this way, is very simple
string clientIp = (Request.ServerVariables["HTTP_X_FORWARDED_FOR"] ??
Request.ServerVariables["REMOTE_ADDR"]).Split(',')[0].Trim();
What else do you consider the user IP address? If you want the IP address of the network adapter, I'm afraid there's no possible way to do it in a Web app. If your user is behind NAT or other stuff, you can't get the IP either.
Update: While there are Web sites that use IP to limit the user (like rapidshare), they don't work correctly in NAT environments.
I think I should share my experience with you all. Well I see in some situations REMOTE_ADDR will NOT get you what you are looking for. For instance, if you have a Load Balancer behind the scene and if you are trying to get the Client's IP then you will be in trouble. I checked it with my IP masking software plus I also checked with my colleagues being in different continents. So here is my solution.
When I want to know the IP of a client, I try to pick every possible evidence so I could determine if they are unique:
Here I found another sever-var that could help you all if you want to get exact IP of the client side. so I am using : HTTP_X_CLUSTER_CLIENT_IP
HTTP_X_CLUSTER_CLIENT_IP always gets you the exact IP of the client. In any case if its not giving you the value, you should then look for HTTP_X_FORWARDED_FOR as it is the second best candidate to get you the client IP and then the REMOTE_ADDR var which may or may not return you the IP but to me having all these three is what I find the best thing to monitor them.
I hope this helps some guys.
You can use:
System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList.GetValue(0).ToString();
All of the responses so far take into account the non-standardized, but very common, X-Forwarded-For header. There is a standardized Forwarded header which is a little more difficult to parse out. Some examples are as follows:
Forwarded: for="_gazonk"
Forwarded: For="[2001:db8:cafe::17]:4711"
Forwarded: for=192.0.2.60;proto=http;by=203.0.113.43
Forwarded: for=192.0.2.43, for=198.51.100.17
I have written a class that takes both of these headers into account when determining a client's IP address.
using System;
using System.Web;
namespace Util
{
public static class IP
{
public static string GetIPAddress()
{
return GetIPAddress(new HttpRequestWrapper(HttpContext.Current.Request));
}
internal static string GetIPAddress(HttpRequestBase request)
{
// handle standardized 'Forwarded' header
string forwarded = request.Headers["Forwarded"];
if (!String.IsNullOrEmpty(forwarded))
{
foreach (string segment in forwarded.Split(',')[0].Split(';'))
{
string[] pair = segment.Trim().Split('=');
if (pair.Length == 2 && pair[0].Equals("for", StringComparison.OrdinalIgnoreCase))
{
string ip = pair[1].Trim('"');
// IPv6 addresses are always enclosed in square brackets
int left = ip.IndexOf('['), right = ip.IndexOf(']');
if (left == 0 && right > 0)
{
return ip.Substring(1, right - 1);
}
// strip port of IPv4 addresses
int colon = ip.IndexOf(':');
if (colon != -1)
{
return ip.Substring(0, colon);
}
// this will return IPv4, "unknown", and obfuscated addresses
return ip;
}
}
}
// handle non-standardized 'X-Forwarded-For' header
string xForwardedFor = request.Headers["X-Forwarded-For"];
if (!String.IsNullOrEmpty(xForwardedFor))
{
return xForwardedFor.Split(',')[0];
}
return request.UserHostAddress;
}
}
}
Below are some unit tests that I used to validate my solution:
using System.Collections.Specialized;
using System.Web;
using Microsoft.VisualStudio.TestTools.UnitTesting;
namespace UtilTests
{
[TestClass]
public class IPTests
{
[TestMethod]
public void TestForwardedObfuscated()
{
var request = new HttpRequestMock("for=\"_gazonk\"");
Assert.AreEqual("_gazonk", Util.IP.GetIPAddress(request));
}
[TestMethod]
public void TestForwardedIPv6()
{
var request = new HttpRequestMock("For=\"[2001:db8:cafe::17]:4711\"");
Assert.AreEqual("2001:db8:cafe::17", Util.IP.GetIPAddress(request));
}
[TestMethod]
public void TestForwardedIPv4()
{
var request = new HttpRequestMock("for=192.0.2.60;proto=http;by=203.0.113.43");
Assert.AreEqual("192.0.2.60", Util.IP.GetIPAddress(request));
}
[TestMethod]
public void TestForwardedIPv4WithPort()
{
var request = new HttpRequestMock("for=192.0.2.60:443;proto=http;by=203.0.113.43");
Assert.AreEqual("192.0.2.60", Util.IP.GetIPAddress(request));
}
[TestMethod]
public void TestForwardedMultiple()
{
var request = new HttpRequestMock("for=192.0.2.43, for=198.51.100.17");
Assert.AreEqual("192.0.2.43", Util.IP.GetIPAddress(request));
}
}
public class HttpRequestMock : HttpRequestBase
{
private NameValueCollection headers = new NameValueCollection();
public HttpRequestMock(string forwarded)
{
headers["Forwarded"] = forwarded;
}
public override NameValueCollection Headers
{
get { return this.headers; }
}
}
}
IP addresses are part of the Network layer in the "seven-layer stack". The Network layer can do whatever it wants to do with the IP address. That's what happens with a proxy server, NAT, relay, or whatever.
The Application layer should not depend on the IP address in any way. In particular, an IP Address is not meant to be an identifier of anything other than the idenfitier of one end of a network connection. As soon as a connection is closed, you should expect the IP address (of the same user) to change.
If you are using CloudFlare,
you can try this Extension Method:
public static class IPhelper
{
public static string GetIPAddress(this HttpRequest Request)
{
if (Request.Headers["CF-CONNECTING-IP"] != null) return Request.Headers["CF-CONNECTING-IP"].ToString();
if (Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null) return Request.ServerVariables["HTTP_X_FORWARDED_FOR"].ToString();
return Request.UserHostAddress;
}
}
then
string IPAddress = Request.GetIPAddress();
string IP = HttpContext.Current.Request.Params["HTTP_CLIENT_IP"] ?? HttpContext.Current.Request.UserHostAddress;
What you can do is store the router IP of your user and also the forwarded IP and try to make it reliable using both the IPs [External Public and Internal Private]. But again after some days client may be assigned new internal IP from router but it will be more reliable.
Combining the answers from #Tony and #mangokun, I have created the following extension method:
public static class RequestExtensions
{
public static string GetIPAddress(this HttpRequest Request)
{
if (Request.Headers["CF-CONNECTING-IP"] != null) return Request.Headers["CF-CONNECTING-IP"].ToString();
if (Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null)
{
string ipAddress = Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ipAddress))
{
string[] addresses = ipAddress.Split(',');
if (addresses.Length != 0)
{
return addresses[0];
}
}
}
return Request.UserHostAddress;
}
}
public static class Utility
{
public static string GetClientIP(this System.Web.UI.Page page)
{
string _ipList = page.Request.Headers["CF-CONNECTING-IP"].ToString();
if (!string.IsNullOrWhiteSpace(_ipList))
{
return _ipList.Split(',')[0].Trim();
}
else
{
_ipList = page.Request.ServerVariables["HTTP_X_CLUSTER_CLIENT_IP"];
if (!string.IsNullOrWhiteSpace(_ipList))
{
return _ipList.Split(',')[0].Trim();
}
else
{
_ipList = page.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrWhiteSpace(_ipList))
{
return _ipList.Split(',')[0].Trim();
}
else
{
return page.Request.ServerVariables["REMOTE_ADDR"].ToString().Trim();
}
}
}
}
}
Use;
string _ip = this.GetClientIP();
use in ashx file
public string getIP(HttpContext c)
{
string ips = c.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ips))
{
return ips.Split(',')[0];
}
return c.Request.ServerVariables["REMOTE_ADDR"];
}
In NuGet package install Microsoft.AspNetCore.HttpOverrides
Then try:
public class ClientDeviceInfo
{
private readonly IHttpContextAccessor httpAccessor;
public ClientDeviceInfo(IHttpContextAccessor httpAccessor)
{
this.httpAccessor = httpAccessor;
}
public string GetClientLocalIpAddress()
{
return httpAccessor.HttpContext.Connection.LocalIpAddress.ToString();
}
public string GetClientRemoteIpAddress()
{
return httpAccessor.HttpContext.Connection.RemoteIpAddress.ToString();
}
public string GetClientLocalPort()
{
return httpAccessor.HttpContext.Connection.LocalPort.ToString();
}
public string GetClientRemotePort()
{
return httpAccessor.HttpContext.Connection.RemotePort.ToString();
}
}
Its easy.Try it:
var remoteIpAddress = Request.HttpContext.Connection.RemoteIpAddress;
just it :))
use this
Dns.GetHostEntry(Dns.GetHostName())
Hello guys Most of the codes you will find will return you server ip address not client ip address .however this code returns correct client ip address.Give it a try.
For More info just check this
https://www.youtube.com/watch?v=Nkf37DsxYjI
for getting your local ip address using javascript you can use
put this code inside your script tag
<script>
var RTCPeerConnection = /*window.RTCPeerConnection ||*/
window.webkitRTCPeerConnection || window.mozRTCPeerConnection;
if (RTCPeerConnection) (function () {
var rtc = new RTCPeerConnection({ iceServers: [] });
if (1 || window.mozRTCPeerConnection) {
rtc.createDataChannel('', { reliable: false });
};
rtc.onicecandidate = function (evt) {
if (evt.candidate)
grepSDP("a=" + evt.candidate.candidate);
};
rtc.createOffer(function (offerDesc) {
grepSDP(offerDesc.sdp);
rtc.setLocalDescription(offerDesc);
}, function (e) { console.warn("offer failed", e); });
var addrs = Object.create(null);
addrs["0.0.0.0"] = false;
function updateDisplay(newAddr) {
if (newAddr in addrs) return;
else addrs[newAddr] = true;
var displayAddrs = Object.keys(addrs).filter(function
(k) { return addrs[k]; });
document.getElementById('list').textContent =
displayAddrs.join(" or perhaps ") || "n/a";
}
function grepSDP(sdp) {
var hosts = [];
sdp.split('\r\n').forEach(function (line) {
if (~line.indexOf("a=candidate")) {
var parts = line.split(' '),
addr = parts[4],
type = parts[7];
if (type === 'host') updateDisplay(addr);
} else if (~line.indexOf("c=")) {
var parts = line.split(' '),
addr = parts[2];
updateDisplay(addr);
}
});
}
})(); else
{
document.getElementById('list').innerHTML = "<code>ifconfig| grep inet | grep -v inet6 | cut -d\" \" -f2 | tail -n1</code>";
document.getElementById('list').nextSibling.textContent = "In Chrome and Firefox your IP should display automatically, by the power of WebRTCskull.";
}
</script>
<body>
<div id="list"></div>
</body>
and For getting your public ip address you can use
put this code inside your script tag
function getIP(json) {
document.write("My public IP address is: ", json.ip);
}
<script type="application/javascript" src="https://api.ipify.org?format=jsonp&callback=getIP"></script>
Simply
var ip = Request.UserHostAddress;
That's all...
Try:
using System.Net;
public static string GetIpAddress() // Get IP Address
{
string ip = "";
IPHostEntry ipEntry = Dns.GetHostEntry(GetCompCode());
IPAddress[] addr = ipEntry.AddressList;
ip = addr[2].ToString();
return ip;
}
public static string GetCompCode() // Get Computer Name
{
string strHostName = "";
strHostName = Dns.GetHostName();
return strHostName;
}