Detect AJAX Request in PHP

Most of the JavaScript frameworks like jQuery, mootools send and additional HTTP_X_REQUESTED_WITH header when they make an AJAX request, so that you can detect AJAX request on server side.

if(!empty($_SERVER[‘HTTP_X_REQUESTED_WITH’])
&& strtolower($_SERVER[‘HTTP_X_REQUESTED_WITH’]) == ‘xmlhttprequest’)
{
  //If AJAX Request Then 
} else { 
  //something else 
}

For More Info http://davidwalsh.name/detect-ajax

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