How to transfer/post byte array using AJAX

How to transfer/post byte array using AJAX

Hi there,

i hope anybody can help me to find the correct way.

I call a function from js in a activex class which return a byte array.

Question one:
Is follow code the correct way to store an byte array in js?
var byteArray = [];
     byteArray = activexfunction()          

Ok should it be correct than i have to post this byteArray over AJAX to a WCF service.

Question two:
What's the correct content-type in ajax settings? Application/binary?

BIG BIG THANKS FOR ANY ADVICES !!!!!