[WP] AJAX or not template

<?php
/* Page requested via AJAX  */
if ( ! empty( $_SERVER['HTTP_X_REQUESTED_WITH'] ) && strtolower( $_SERVER['HTTP_X_REQUESTED_WITH'] ) == 'xmlhttprequest' ) {

    // the loop
    if ( have_posts() ) : while ( have_posts() ) : the_post();
        // template tags
    endwhile; endif;

/* Page requested via regular HTTP */
} else {

    get_header()

    // the loop
    if ( have_posts() ) : while ( have_posts() ) : the_post();
        // template tags
    endwhile; endif;

    get_footer();

}