ช่วยดูให้ทีค่ะ พอตอนรันมันไม่เช็ค ตามที่เราเขียนโค้ดไว้ค่ะ ไม่ทราบว่าเป็นเพราะอะไร

<script type="text/javascript">
function checkData(frmMain){
	var errstyle = document.getElementById("errstyle");
	var errtype = document.getElementById("errtype");
	var errfee = document.getElementById("errfee");
	var errzone = document.getElementById("errzone");
	// clear error
	errstyle.innerHTML="";
	errtype.innerHTML="";
	errfee.innerHTML="";
	errzone.innerHTML="";
	var chk=true;
		if(frmMain.id_style.value == ""){
			errstyle.innerHTML="*   ";
			frmMain.id_style.focus();
			chk=false;
		}if(frmMain.id_type.value == ""){
			errtype.innerHTML="*   ";
			frmMain.id_type.focus();
			chk=false;
		}if(frmMain.id_fee.value == ""){
			errfee.innerHTML="*   ";
			frmMain.id_fee.focus();
			chk=false;
		}if(frmMain.id_zone.value == ""){
			errzone.innerHTML="*   ";
			frmMain.id_zone.focus();
			chk=false;
		}
		return chk;
	}
</script>

         <td bgcolor="#FFCCCC"><form name="frmMain" method="post" action="show.php" onsubmit="return checkData(this);">
    <p>&nbsp;</p>
    <table width="436" border="0" align="center" bgcolor="#FFFFFF">
  <tr>
    <td width="188"><div align="right"><font color="#FF0000"><span id="errstyle"></span></font>
    <strong>รูปแบบการท่องเที่ยว :</strong> </div></td>
    <td width="238"><p>
	<select id="id_style" name="id_style" onChange ="ListType(this.value)">
	<option selected value="">&nbsp;&nbsp;&nbsp;&nbsp;- - - - เลือกรูปแบบ - - - -</option>
	<?
	$strSQL = "SELECT * FROM style ORDER BY id_style";
	$objQuery = mysql_query($strSQL) or die ("Error Query [".$strSQL."]");
	while($objResult = mysql_fetch_array($objQuery))
	{
	?>
	<option value="<?=$objResult["id_style"];?>"><?=$objResult["name_style"];?></option>
	<?
	}
	?>
	</select>
    </p></td>
   </tr>
   <tr>
    <td width="188"><div align="right"><font color="#FF0000"><span id="errtype"></span></font>
    <strong>หมวดหมู่สถานที่ :</strong> </div></td>
    <td width="238"><p>
	<select id="id_type" name="id_type" style="width:220px">
    </select>
    </p></td>
    </tr>
   <tr>
     <td valign="top"><div align="right"><br><font color="#FF0000"><span id="errfee"></span></font>
     <strong>ค่าใช้จ่ายในการเข้าชม :</strong> </div></td>
     <td><p>
	 <?
    $sql = "SELECT * FROM fee";
	$result = mysql_query($sql);
	while ($dbarr = mysql_fetch_array($result)) 
	{
	?>
		<p><input name="id_fee" type="radio" value=<?=$dbarr["id_fee"];?> /><?=$dbarr["name_fee"];?></p>
		
    <?    
	}
    ?>
    </p></td>
   </tr>
   <tr>
     <td valign="top"><div align="right"><br><font color="#FF0000"><span id="errzone"></span></font>
     <strong>สถานที่ตั้ง :</strong> </div></td>
     <td><p>
    <?
    $sql = "SELECT * FROM zone";
	$result = mysql_query($sql);
	while ($dbarr = mysql_fetch_array($result)) 
	{
	?>
		<p><input name="id_zone" type="radio" value=<?=$dbarr["id_zone"];?> /><?=$dbarr["name_zone"];?></p>	
        <p>
    <?    
	}
    ?>
        </p></td>
   </tr>
  <tr>
    <td colspan="2" align="center">
      <p>
        <label>
        <input type="image" name="imageField" id="imageField" src="images/submit.jpg"/>
        </label>
        <label for="imageField2"></label>
      </form>
      </p></td>
    </tr>
</table>