เขียน javascript อย่างไรให้แสดงผลโดยไม่ต้องกด submit

<?php include('connect.php'); ?>


   <!-- เนื้อหา -->
      <div class="content-wrapper">
        <!-- Content Header (Page header) -->

        <section class="content-header">
          <h1>
             แก้ไขข้อมูล
           
          </h1>
          
        </section>

        <!-- Main content -->
        <section class="content">
		<form class="form-horizontal" method="post"   >
                        <div class="box-body"> 
                        
                        
                        
<script language="javascript">
function fncCal()
{
	document.form1.quotation_total.value = parseInt(document.form1.quotation_qty.value) * parseInt(document.form1.quotation_distcount.value)
}
</script>                   
                        
                        
                        
                          
   <?php
        if(isset($_GET['quotation_id']))
        {
          $quotation_id=$_GET['quotation_id'];
          $sql=" select * from tb_quotation";
          $sql.=" where quotation_id=$quotation_id";
          $result=$cls_con->select_base($sql);
          while ($row=mysqli_fetch_array($result)) 
          {
            $quotation_id=$row['quotation_id'];
            $quotation_no=$row['quotation_no'];
            $quotation_status=$row['quotation_status'];			
            $quotation_qty=$row['quotation_qty'];
			$quotation_total=$row['quotation_total'];
			$quotation_distcount=$row['quotation_distcount'];
			$pro_price=$row['pro_price'];
			
          }

        }

        ?>
        
        <form action="page.cgi" method="post" name="form1">
               
                  <div class="box-body">
                        
                      <input type="hidden" name="quotation_id" value="<?=$quotation_id;?>" />
                      <div class="form-group">
                      <label for="quotation_status" class="col-sm-2 control-label">สถานะ</label>
                      <div class="col-sm-10">
                        <input readonly class="form-control" name="quotation_status" value="<?=$quotation_status;?>" id="quotation_status" placeholder="">
                      </div>
                    </div>
                      
                    <div class="form-group">
                      <label for="quotation_no" class="col-sm-2 control-label">เลขที่ใบเสนอราคา</label>
                      <div class="col-sm-10">
                        <input readonly class="form-control" name="quotation_no" value="<?=$quotation_no;?>" id="quotation_no" placeholder="">
                      </div>
                    </div>

                       <div class="form-group">
                      <label for="quotation_qty" class="col-sm-2 control-label">จำนวนเดิม</label>
                      <div class="col-sm-10">
                      <input readonly class="form-control" name="quotation_qty" value="<?=$quotation_qty;?>"  id="quotation_qty" placeholder="">
                      </div>
                    </div>
					
					
					<div class="form-group">
                      <label for="quotation_qty" class="col-sm-2 control-label">จำนวนใหม่</label>
                      <div class="col-sm-10">
                      <input name="quotation_qty" id="quotation_qty" type="text" OnKeyUp="fncCal();">
                      
                      </div>
                    </div>
                    
                    <div class="form-group">
                      <label for="quotation_distcount" class="col-sm-2 control-label">ส่วนลด(%) เดิม</label>
                      <div class="col-sm-10">
                        <input readonly class="form-control" name="quotation_distcount" value="<?=$quotation_distcount;?>"  id="quotation_distcount" placeholder="">
                      </div>
                    </div>
					<div class="form-group">
                      <label for="quotation_distcount" class="col-sm-2 control-label">ส่วนลด(%) ใหม่</label>
                      <div class="col-sm-10">
                      <input name="quotation_distcount" id="quotation_distcount" type="text" OnKeyUp="fncCal();">
                      
                      </div>
                    </div>
                    <div class="form-group">
                      <label for="pro_price" class="col-sm-2 control-label">ราคา/หน่วย</label>
                      <div class="col-sm-10">
                        <input readonly class="form-control" name="pro_price" value="<?=$pro_price;?>"  id="pro_price" placeholder="">
                      </div>
                    </div>

					<div class="form-group">
                      <label for="quotation_total" class="col-sm-2 control-label">ราคารวมก่อน VAT</label>
                      <div class="col-sm-10">
                       <input name="quotation_total" id="quotation_total" type="text" readonly><br>
                       
                     
                       </div>
                      </div>
                      <div class="form-group">
                      <label for="quotation_vat" class="col-sm-2 control-label">มูลค่า VAT</label>
                      <div class="col-sm-10">
                        <input readonly class="form-control" name="quotation_vat" id="quotation_vat" placeholder="">
                        </div>
                        </div>
                      <div class="form-group">
                      <label for="quotation_total3" class="col-sm-2 control-label">ราคารวม VAT</label>
                      <div class="col-sm-10">
                        <input readonly class="form-control" name="quotation_total3" id="quotation_total3" placeholder="">
                        </div>
                        </div>    

                  </div><!-- /.box-body -->
                  <center>
                    <button type="submit" name="submit" class="btn btn-info">บันทึก</button>
                    <input name="reset" type="reset" id="reset" value="ยกเลิก" onClick="window.location.href='show_quotationitem.php';" class="btn btn-warning">                 
                </center>
                </form>
                <?php
                        if(isset($_POST['submit']))
                        {
                            $quotation_id=$_POST['quotation_id'];
                            $quotation_no=$_POST['quotation_no'];
                            $quotation_distcount=$_POST['quotation_distcount'];
                            $quotation_qty=$_POST['quotation_qty'];
							$quotation_total=$_POST['quotation_total'];
							

                            $sql=" update tb_quotation";
                            $sql.=" set";
							//$sql.=" quotation_total='$quotation_total'";
                            $sql.=" quotation_no='$quotation_no',";
							
                            $sql.=" quotation_distcount='$quotation_distcount',";
							
					        $sql.=" quotation_qty='$quotation_qty'"; 
							 
							
							                         
                            $sql.=" where";     
                            $sql.=" quotation_id='$quotation_id'";      
                            
                            if($cls_con->write_base($sql)==true)
                            {
                                echo $cls_con->show_message('แก้ไขข้อมูลสำเร็จ');
                                echo $cls_con->goto_page(1,'show_quoitem.php');
                            }
                            else
                            {
                                 echo $cls_con->show_message('แก้ไขข้อมูลไม่สำเร็จ');
                                 echo $sql;
                            }
                        }
                        
                        ?>

        </section><!-- /.content -->
      </div>
      <!-- เนื้อหา -->
       
<?php include('footer.php'); ?>