if(Context.Request.ServerVariables["HTTP_VIA"]!=null) // 服务器, using proxy
{
得到真实的客户端地址
ip=Context.Request.ServerVariables["HTTP_X_FORWARDED_FOR"].ToString(); // Return real client IP.
}
else//如果没有使用代理服务器或者得不到客户端的ip not using proxy or can't get the Client IP
{
//得到服务端的地址
ip=Context.Request.ServerVariables["REMOTE_ADDR"].ToString(); //While it can't get the Client IP, it will return proxy IP.
}