ช่วยดูโค้ดให้ทีครับผมเลือกจาก menu list แล้วให้มันโชว์อัตโนมัติ

    <script language="JavaScript">
	function resutName(id_employee_type)
	{
		switch(id_employee_type)
		{
			<?php
			$result3 = mysql_query("SELECT * FROM employee_type ");
			while($row3 = mysql_fetch_array($result3))
			{
			?>
				case "<?=$row3["id_employee_type"];?>":
				form1.detail_type.value = "<?=$row3["detail_type"];?>";
				break;
				
			<?php
			}
			?>
			default:
			 form1.detail_type.value = "";
		}
	}
</script>

  <select name="id_employee_type" OnChange="resutName(this.value);" >
        <? $result3 = mysql_query("SELECT * FROM employee_type");
		while($row3 = mysql_fetch_array($result3))
  { ?>
		<option value="<?=$row3["id_employee_type"]?>"><?=$row3['type_employee']?></option>
       
  <? } ?>
      </select></td>
      </tr>
      <tr>
        <td align="right" valign="top" bgcolor="#EAEAEA">รายละเอียดการรับสมัคร :</td>
        <td bgcolor="#EAEAEA"><textarea name="detail_type" cols="50" rows="5" disabled="disabled" readonly="readonly" id="<?=$row3['detail_type']?> " ></textarea></td>