How to catch headers using JavaScript?

Hello friends,

I am not sure if this is a right place to find the solution..... please bear with me but i guess it must be possible using javascript..

I want to catch the headers sent by a webpage or website for. e.g. a php sets headers using
<?
header("content-type: #####");
header("blahblah: #####");
header("blahblah: #####");
?>

now i want to track those using either javascript or some client side process to check the encryption type used....

Thanks for you time ... IF i am missing to provide some information please correct me ....

 

To my knowledge, you can't use JavaScript for this.

 

any suggestion for correct methodology ? to make it work .. the basic reason i am looking for it is I wanna study different websites which are in different languages and for that i need to understand what kind of character encoding they are using .

thanks for your reply