Fragen zu Adsense Plugin

$adsense_code = '
<!-- Begin Google Adsense code -->
<div style="float: left;margin: 4px;">
<script type="text/javascript"><!--
google_ad_client = "pub-";
google_ad_slot = "";
google_ad_width = 300;
google_ad_height = 250;
//--></script>
<script type="text/javascript"
src="[URL]http://pagead2.googlesyndication.com/pagead/show_ads.js[/URL]">
</script>
</div>
<!-- End Google Adsense code -->
'; 
/**************************************************************************
** All done!  No more changes need to be made below this line!           **
**************************************************************************/
 if (is_single()) {
  return $adsense_code . $data ;
 } else {
     return $data ;
 }
} 
add_filter('the_content', 'insert_adsense_code');