juipnet/Infrastructure/Hncore.Infrastructure/Common/NetworkHelper.cs

using System.Linq;
using System.Net;
using System.Net.NetworkInformation;
using System.Net.Sockets;

namespace Hncore.Infrastructure.Common
{
    public class NetworkHelper
    {
        public static string GetPublicIp()
        {
            return NetworkInterface
                .GetAllNetworkInterfaces()
                .Select(p => p.GetIPProperties())
                .SelectMany(p => p.UnicastAddresses)
                .FirstOrDefault(p =>
                    p.Address.AddressFamily == AddressFamily.InterNetwork && !IPAddress.IsLoopback(p.Address))?.Address
                .ToString();
        }
    }
}