แก้ไขข้อมูล Listmenu multiple จากฐานข้อมูล mysql

              <select name="ref_listproduct_id[]"size="5" multiple="MULTIPLE">
              <option value="" >-เลือก-</option>
              <?php 
                   $sql4  = "select * from listproduct";
                   $query4 = mysql_query($sql4)or die("ERROR=$sqlp");
                   $num4   = mysql_num_rows($query4);

                   for($i=1;$i<=$num4;$i++)
                   {
                       $row4 =mysql_fetch_array($query4); 			   	
					   
                                        
                ?>
          		<option value="<? echo $row4['listpro_id']?>"
				<?php if ($arr['listpro_id']==$row4['listpro_id'] ){echo 'selected="selected"';}?>>
		  		<? echo $row4['listpro_name'];?></option>
			   <?
                   }
                ?>
        		</select>

<select name="select" id="select">
	<option value="">- เลือก -</option>
<?
     $sql="SELECT * FROM listproduct";
     $query=mysql_query($sql);
     while($row4=mysql_fetch_array($query)){
          echo '<option value="'.$row4["listpro_id"].'">'.$row4["listpro_name"].'</option>';
     }
?>
</select>