ASP.NET获取IP地址

public static string GetRealIP()
{
     string result = System.Web.HttpContext.Current.Request.Headers["Cdn-Src-Ip"];
     if(string.IsNullOrEmpty(result))
      {
          result = System.Web.HttpContext.Current.Request.Headers["HTTP_X_FORWARDED_FOR"];
      }
      if(string.IsNullOrEmpty(result))
       {
         result = System.Web.HttpContext.Current.Request.Headers["HTTP_VIA"];
       }
       if(string.IsNullOrEmpty(result))
       {
          result = System.Web.HttpContext.Current.Request.Headers["REMOTE_ADDR"];
       }
      if(string.IsNullOrEmpty(result)||!IsIp(result))
       {
            result = "127.0.0.1";
       }
       return result;
}

/// <summary>
///是否为ip
/// </summary>
/// <param name="ip"></param>
/// <returns></returns>
public static bool IsIp(string ip)
{
   return Regex.IsMatch(ip, @"^((2[0-4]\d|25[0-5]|[01]?\d\d?)\.){3}(2[0-4]\d|25[0-5]|[01]?\d\d?)$");
}