备份一下~

        /// <summary>
        /// 获取IP地址
        /// </summary>
        public static string IPAddress
        {
            get 
            {
                string ipAddress = "000.000.000.000";
                try
                {
                    // 有可能是后台调用
                    HttpContext context = HttpContext.Current;                
                    ipAddress = GetUserIpAddress(context);
                }
                catch{}
                return ipAddress;
            }
        }

        /// <summary>
        /// 透过代理获取真实IP
        /// </summary>
        /// <param name="context"></param>
        /// <returns></returns>
        public static string GetUserIpAddress(HttpContext context)
        {
            string result = String.Empty;
            if (context == null) 
                return result;

            // 透过代理取真实IP
            result = HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
            if (null == result || result == String.Empty)
                result = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
            
            if (null == result || result == String.Empty)
                result = HttpContext.Current.Request.UserHostAddress;

            return result;
        }