接收有关其他域创建的Cookie数量的信息

User visit my site and type into input address of his site. JQuery send AJAX request to my PHP script and now: how this PHP script can check the amount of cookies which this domain creates (domain from input) ?

Thanks for help.

You need to check the headers of the connection you create from your server to his website. Every cookie will be a header starting with:

Set-cookie: ...

You can look into the use of cURL in PHP and CURLOPT_NOBODY. The user manual is here.