AilisidanShow.Helper.GetIpHelper.GetRealIP C# (CSharp) Method

        public static string GetRealIP()
        {
            string result = String.Empty;
            result = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
            //可能有代理
            if (!string.IsNullOrWhiteSpace(result))
            {
                //没有"." 肯定是非IP格式
                if (result.IndexOf(".") == -1)
                {
                    result = null;
                }
                else
                {
                    //有","，估计多个代理。取第一个不是内网的IP。
                    if (result.IndexOf(",") != -1)
                    {
                        result = result.Replace(" ", string.Empty).Replace("\"", string.Empty);

                        string[] temparyip = result.Split(",;".ToCharArray());

                        if (temparyip != null && temparyip.Length > 0)
                        {
                            for (int i = 0; i < temparyip.Length; i++)
                            {
                                //找到不是内网的地址
                                if (IsIPAddress(temparyip[i]) && temparyip[i].Substring(0, 3) != "10." && temparyip[i].Substring(0, 7) != "192.168" && temparyip[i].Substring(0, 7) != "172.16.")
                                {
                                    return temparyip[i];
                                }
                            }
                        }
                    }
                    //代理即是IP格式
                    else if (IsIPAddress(result))
                    {
                        return result;
                    }
                    //代理中的内容非IP
                    else
                    {
                        result = null;
                    }
                }
            }

            if (string.IsNullOrWhiteSpace(result))
            {
                result = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
            }

            if (string.IsNullOrWhiteSpace(result))
            {
                result = System.Web.HttpContext.Current.Request.UserHostAddress;
            }
            return result;
        }