PHP check whether Incoming Request is JSON type

Question

Is there anyway to check whether an incoming request is of AJAX JSON type?

I tried

if(($_SERVER[\'REQUEST_METHOD\']==\'JSON\'))
{
}

Answer 1

You would need to set a header from the client side. jQuery and other libraries set a x-requested-with header:

if(strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest')
{
   echo "Ajax request";
}