如何在MVC中获取客户端ip地址

Question

I would like to pull out the client's PC's IP address. I have tried below approaches but it always returns "::1"

1. var test = this.Request.ServerVariables.Get("REMOTE_ADDR");

2. request.UserHostAddress;

Any inputs?

Answer 1

You can get the IP address like this in your Controller method:

If the client machine is behind a proxy server, we can check for the variable HTTP_X_FORWARDED_FOR :

string ip;
ip =  System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (string.IsNullOrEmpty(ip))
{
    ip =  System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
}

If the IP Address is not found in the HTTP_X_FORWARDED_FOR server variable, it means that it is not using any Proxy Server and hence the IP Address is now checked in the REMOTE_ADDR server variable.

Note: On your local machine, the IP address will be shown as ::1 which is an IPV6 loopback address (ie localhost). An IPV4 address would be 127.0.0.1 .

This is because in such case the Client and Server both are the same machine. When the application is deployed on the server, then the result will be different.

Answer 2

The below code should give you collection of client IP Addresses. If not, please post your code snippet so we can verify:

public static System.Collections.Generic.IReadOnlyCollection<System.Net.IPAddress> GetIpAddresses()
{
    var ipAddresses = new List<System.Net.IPAddress>();

    foreach (var values in GetValues(System.Web.HttpContext.Current.Request.Headers, "X-Forwarded-For"))
    {
        foreach (var ipv in values.Split(new char[] { ',', ' ', '\t', '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries))
        {
            if (ipv.Contains(":"))
            {
                var array = ipv.Split(':');
                ipAddresses.Add(array.Length == 2 ? System.Net.IPAddress.Parse(array[0].Trim()) : System.Net.IPAddress.Parse(ipv.Trim()));
            }
            else
            {
                ipAddresses.Add(System.Net.IPAddress.Parse(ipv));
            }
        }
    }

    if (request.UserHostAddress != null)
    {
        if (request.UserHostAddress.Contains(":"))
        {
            var array = request.UserHostAddress.Split(':');
            ipAddresses.Add(array.Length == 2 ? System.Net.IPAddress.Parse(array[0].Trim()) : System.Net.IPAddress.Parse(request.UserHostAddress.Trim()));
        }
        else
        {
            ipAddresses.Add(System.Net.IPAddress.Parse(request.UserHostAddress));
        }
    }
    return ipAddresses;
}