ASP.NET MVC獲取web客戶端ip

需要引用using System.Web;

 /// <summary>
        /// 獲取web客戶端ip
        /// </summary>
        /// <returns></returns>
        public static string GetWebClientIp()
        {          
            string CustomerIP = "";
            try
            {
                if (System.Web.HttpContext.Current == null
                 || System.Web.HttpContext.Current.Request == null
                 || System.Web.HttpContext.Current.Request.ServerVariables == null)
                {
                    return "";
                }
                //CDN加速後取到的IP
                CustomerIP = System.Web.HttpContext.Current.Request.Headers["Cdn-Src-Ip"];
                if (!string.IsNullOrEmpty(CustomerIP))
                {
                    return CustomerIP;
                }
                CustomerIP = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
                if (!String.IsNullOrEmpty(CustomerIP))
                {
                    return CustomerIP;
                }
                if (System.Web.HttpContext.Current.Request.ServerVariables["HTTP_VIA"] != null)
                {
                    CustomerIP = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
                    if (CustomerIP == null)
                    {
                        CustomerIP = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
                    }
                }
                else
                {
                    CustomerIP = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
                }

                if (string.Compare(CustomerIP, "unknown", true) == 0 || String.IsNullOrEmpty(CustomerIP))
                {
                    return System.Web.HttpContext.Current.Request.UserHostAddress;
                }
            }
            catch { CustomerIP = "0.0.0.0"; }
            return CustomerIP == "::1" ? "0.0.0.0" : CustomerIP;
        }