获得IP地址

.net Core

获得服务器本地的IP地址：注意，不是获得客户端IP地址

string IP = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList.FirstOrDefault(address => address.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)?.ToString();

获得客户端IP地址：

    /// <summary>
    /// 扩展类
    /// </summary>
    public static class Extension
    {
        /// <summary>
        /// 获取客户Ip
        /// </summary>
        /// <param name="context"></param>
        /// <returns></returns>
        public static string GetClientUserIp(this HttpContext context)
        {
            var ip = context.Request.Headers["X-Forwarded-For"].FirstOrDefault();
            if (string.IsNullOrEmpty(ip))
            {
                ip = context.Connection.RemoteIpAddress.ToString();
            }
            return ip;
        }
    }

string IP = HttpContext.GetClientUserIp();

　　解决Asp.Net Core2.0发布到Ubuntu后不能正确获取客户IP解决办法

　　

/// <summary>
/// 
/// </summary>
/// <param name="app"></param>
/// <param name="env"></param>
/// <param name="loggerFactory"></param>
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
    #region 解决Ubuntu Nginx 代理不能获取IP问题
    app.UseForwardedHeaders(new ForwardedHeadersOptions
    {
        ForwardedHeaders = ForwardedHeaders.XForwardedFor | ForwardedHeaders.XForwardedProto
    });
    #endregion       
}

.NetFramework

 public static class HttpRequestMessageExtensions
    {
        private const string HttpContext = "MS_HttpContext";
        private const string RemoteEndpointMessage =
            "System.ServiceModel.Channels.RemoteEndpointMessageProperty";
        private const string OwinContext = "MS_OwinContext";

        public static string GetClientIpAddress(this HttpRequestMessage request)
        {
            // Web-hosting. Needs reference to System.Web.dll
            if (request.Properties.ContainsKey(HttpContext))
            {
                dynamic ctx = request.Properties[HttpContext];
                if (ctx != null)
                {
                    return "" + ctx.Request.UserHostAddress;
                }
            }

            // Self-hosting. Needs reference to System.ServiceModel.dll. 
            if (request.Properties.ContainsKey(RemoteEndpointMessage))
            {
                dynamic remoteEndpoint = request.Properties[RemoteEndpointMessage];
                if (remoteEndpoint != null)
                {
                    return "" + remoteEndpoint.Address;
                }
            }

            // Self-hosting using Owin. Needs reference to Microsoft.Owin.dll. 
            if (request.Properties.ContainsKey(OwinContext))
            {
                dynamic owinContext = request.Properties[OwinContext];
                if (owinContext != null)
                {
                    return "" + owinContext.Request.RemoteIpAddress;
                }
            }

            return null;
        }
    }