asp.net 返回电脑真实IP地址

public static string getIP()
        {
            string result = String.Empty;
            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;
            }
            if (null == result || result == String.Empty)
            {
                return "0.0.0.0";
            }
            return result;
        }