<?php
if (has_post_thumbnail()) {
$image_url = wp_get_attachment_image_src(get_post_thumbnail_id(), 'thumbnail'); 
//resim boyutu: thumbnail, medium, large, full veya functions.php den özel belirlenmiş olabilir.	
?>
<a href="<?php echo $image_url[0];?>">
<img class="image-thumb" src="<?php echo $image_url[0];?>" alt="<?php the_title(); ?>" />
</a>
<?php } ?>