- strpos: documentation ( source)
<?php
$url = $_SERVER["REQUEST_URI"];
if (strpos($url, "multi-pdf") !== false) {
$showIcon = " . esc_url( get_header_image() ) . " ;
}else {
$showIcon = "http://batchpdfmerger.com/images/icon.png" ;
}
if ( get_header_image() != '' ) { echo 'style="background-image: url($showIcon);"'; }