<script>
function showDetails( ) {
alert($sak);
return true;
}
</script>

<?php  while ($user_field = mysql_fetch_assoc($userdata))    {$sak=$user_field['uid'];?>
<a href="edit.php?myid=<?php print $user_field['uid']; ?>">Edit</a>&nbsp;<a      href="#" onClick="showDetails('<?php echo $sak; ?>');">Delete</a>
}