php - Javascript Error "Null is not an Object" with a dynamically created html table -

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i have dynanamically created html table picture in last cell of each row (like.png). achieve after user has clicked on picture 1 diplayed (like1.png). keep getting "null not object", there maybe wrong javascript code ...

thank :)

here php creates table :

<?php $pictureid = 1;              while($results = mysql_fetch_array($raw_results)){             // $results = mysql_fetch_array($raw_results) puts data database array, while it's valid loop              echo '<tr>';             echo'<td>'. ucfirst($results['song_name']).'</td>';             echo'<td>'. ucfirst($results['song_artist']).'</td>';             //echo'<td>'. ucfirst($results['song_album']).'</td>';                  echo '<td>';                  echo  '<img src="images/like.png" id="artist'.$pictureid.'" onclick="action(artist'.$pictureid.')"/></a>';                 echo '</td>';                  echo '</tr>';                  $pictureid = $pictureid + 1;                  }

and here javascript :

<script language="javascript">    function action(imageid) { if(document.getelementbyid(imageid).src == 'like.png' ) document.getelementbyid(imageid).src = 'like1.png'; else document.getelementbyid(imageid).src = 'like1.png'; } </script>

you're missing quotes here:

echo  '<img ... onclick="action(\'artist'.$pictureid.'\')"/></a>'; // quotes missing here ----------^---------------------^

in output html should like, e.g., this:

<img ... onclick="action(artist1)"/>

this call method action() , use variable of name artist1, not exists. in method document.getelementbyid() returns null , error.

your method, however, requires string input , should enclose parameter quotes, generates output this:

<img ... onclick="action('artist1')"/>

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