Check ค่าไงดี สงสัยเรื่องการ check ค่าถ้าเป็น textbox แล้วกดปุ่มเพื่อส่งค่าไปอีกหน้านึง

function CheckData(){
		var name=document.getElementById("name").value;
	var surname=document.getElementById("surname").value;
	
	
	if(  name !="" &&  surname !="")
		return true;
	else{
		alert("คุณกรอกข้อมูลไม่ครบ กรุณาตรวจสอบข้อมูลอีกครั้ง");
		return false;
	}
}
<table>
 <tr align="left">
    <td class="narmal3old">Name::</td>
    <td><input name="name" type="text" id="name" size="25" maxlength="20" /></td>
    <td>&nbsp;</td>
  </tr>
 <tr align="left">
    <td class="narmal3old">Surname::</td>
    <td><input name="surname" type="text" id="surname" size="25" maxlength="50" /></td>
    <td>&nbsp;</td>
  </tr>
  <tr>
    <td colspan="3"><div align="center">
      <input type="submit" name="Submit" value="Confirm"  onClick="return CheckData()"/>
    </div></td>
    </tr>
</table>

 <? 

  if(isset($_POST["id_product"])){
	
						foreach($_POST["id_product"] as $a => $value){
								$item[$k] = $value;
								echo "<input type='hidden' name='item[]' value='$value'>"; 
								$sql = mysql_query("select * from Product where ID_pro = '$item[$k]'");
								$numm = mysql_num_rows($sql);
								while($result = mysql_fetch_array($sql)){
					
  ?>
  <tr>
    <td rowspan="3">&nbsp;</td>
    <td rowspan="3"> <? echo "<img src='../admin/Product/images_product/".$result['Image_Pro']."' width='150' height='142'>";?></td>
    <td><div align="left"><span class="style11"><? echo $result['Name_Pro'];?></span>
      </div></td>
    <td rowspan="3"><div align="center">
     <input name="Q[]" type="text" id="Q[]" maxlength="3" />
    </div></td>
   
  </tr>
 
  <tr>
    <td><div align="left"><span class="style12">Price::</span> <? echo $result['Price_Pro'];?>
      </div></td>
    </tr>
  <tr>
    <td><div align="left"><span class="style13">Detail::</span> <? echo $result['Detail_Pro'];?>
      </div></td>
    </tr>
  <tr>
    <td colspan="5"><hr /></td>
    </tr>
	 <? } } }?>