我已经在php上构建了POS系统，并面临一个非常有趣的问题。我可以在销售通知单上添加多达20个项目，并将其存储在数据库中，我们可以检索并打印它，但是每当我打印它时，它总会出现在2页而不是一页中，即使有一件，其余的值是null。有没有办法强制在一页上打印？
代码如下：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Print Invoice - Chara Motor Servicing</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<link rel="stylesheet" type="text/css" href="bootstrap/css/bootstrap.min.css" />
<link rel="stylesheet" type="text/css" href="font-awesome/css/font-awesome.min.css" />
<script type="text/javascript" src="js/jquery-1.10.2.min.js"></script>
<script type="text/javascript" src="bootstrap/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<div class="container">
<div class="row">
<div class="col-xs-12">
<div class="text-center">
<h3>Chara Motor Servicing</h3>
<h4>Address Line 1</h4>
<h4>Telephone: 000000000000</h4>
<h4>GSTIN: XXXXXXXXXXXXXXX</h4>
</div>
<hr>
<?php
include 'database_connection.php';
$data=$_GET['invoice_id'];
$user_id=$data;
$sql = "SELECT `name`, `phone`, `town`, `date`, `item1`, `item2`, `item3`, `item4`, `item5`, `item6`, `item7`, `item8`,`item9`, `item10`, `item11`, `item12`, `item13`, `item14`, `item15`, `item16`,`item17`, `item18`, `item19`, `item20`, `item21`, `item22`, `q1`, `q2`, `q3`, `q4`, `q5`, `q6`, `q7`, `q8`,`q9`, `q10`, `q11`, `q12`, `q13`, `q14`, `q15`, `q16`,`q17`, `q18`, `q19`, `q20`, `q21`, `q22`, `taxper`, `amt1`, `amt2`, `amt3`, `amt4`, `amt5`, `amt6`, `amt7`, `amt8`, `amt9`, `amt10`, `amt11`, `amt12`, `amt13`, `amt14`, `amt15`, `amt16`,`amt17`, `amt18`, `amt19`, `amt20`, `amt21`, `amt22`,`taxtotal`, `subtotal`, `status` FROM `sales` WHERE id=$user_id";
$result = $conn->query($sql);
while ($row = mysqli_fetch_array($result)):
?>
<div class="row">
<div class="col-xs-12 col-md-3 col-lg-3 pull-left">
<div class="panel panel-default height">
<div class="panel-heading">Invoiced To: </div>
<div class="panel-body">
<strong><?php echo $row['name']; ?></strong><br>
<?php echo $row['phone']; ?><br>
<?php echo $row['town']; ?><br>
<?php echo $row['date']; ?><br>
<strong>Invoice#: <?php echo $user_id; ?><br> </strong>
<strong><?php echo $row['status']; ?><br> </strong><br>
<button class="btn btn-primary hidden-print" onclick="myFunction()"><span class="glyphicon glyphicon-print" aria-hidden="true"></span> Print</button>
</div>
</div>
</div>
</div>
</div>
</div>
<div class="row">
<div class="col-md-12">
<div class="panel panel-default">
<div class="panel-heading">
<h3 class="text-center"><strong>Order Summary</strong></h3>
</div>
<div class="panel-body">
<div class="table-responsive">
<table class="table table-condensed">
<thead>
<tr>
<td><strong>Item Name</strong></td>
<td class="text-center"><strong>Item Quantity</strong></td>
<td class="text-right"><strong>Total Price</strong></td>
</tr>
</thead>
<tbody>
<tr>
<td><?php echo $row['item1']; ?></td>
<td class="text-center"><?php echo $row['q1']; ?></td>
<td class="text-right"><?php echo $row['amt1']; ?></td>
</tr>
<tr>
<td><?php echo $row['item2']; ?></td>
<td class="text-center"><?php echo $row['q2']; ?></td>
<td class="text-right"><?php echo $row['amt2']; ?></td>
</tr>
<tr>
<td><?php echo $row['item3']; ?></td>
<td class="text-center"><?php echo $row['q3']; ?></td>
<td class="text-right"><?php echo $row['amt3']; ?></td>
</tr>
<tr>
<td><?php echo $row['item4']; ?></td>
<td class="text-center"><?php echo $row['q4']; ?></td>
<td class="text-right"><?php echo $row['amt4']; ?></td>
</tr>
<tr>
<td><?php echo $row['item5']; ?></td>
<td class="text-center"><?php echo $row['q5']; ?></td>
<td class="text-right"><?php echo $row['amt5']; ?></td>
</tr>
<tr>
<td><?php echo $row['item6']; ?></td>
<td class="text-center"><?php echo $row['q6']; ?></td>
<td class="text-right"><?php echo $row['amt6']; ?></td>
</tr>
<tr>
<td><?php echo $row['item7']; ?></td>
<td class="text-center"><?php echo $row['q7']; ?></td>
<td class="text-right"><?php echo $row['amt7']; ?></td>
</tr>
<tr>
<td><?php echo $row['item8']; ?></td>
<td class="text-center"><?php echo $row['q8']; ?></td>
<td class="text-right"><?php echo $row['amt8']; ?></td>
</tr>
<tr>
<td><?php echo $row['item9']; ?></td>
<td class="text-center"><?php echo $row['q9']; ?></td>
<td class="text-right"><?php echo $row['amt9']; ?></td>
</tr>
<tr>
<td><?php echo $row['item10']; ?></td>
<td class="text-center"><?php echo $row['q10']; ?></td>
<td class="text-right"><?php echo $row['amt10']; ?></td>
</tr>
<tr>
<td><?php echo $row['item11']; ?></td>
<td class="text-center"><?php echo $row['q11']; ?></td>
<td class="text-right"><?php echo $row['amt11']; ?></td>
</tr>
<tr>
<td><?php echo $row['item12']; ?></td>
<td class="text-center"><?php echo $row['q12']; ?></td>
<td class="text-right"><?php echo $row['amt12']; ?></td>
</tr>
<tr>
<td><?php echo $row['item13']; ?></td>
<td class="text-center"><?php echo $row['q13']; ?></td>
<td class="text-right"><?php echo $row['amt13']; ?></td>
</tr>
<tr>
<td><?php echo $row['item14']; ?></td>
<td class="text-center"><?php echo $row['q14']; ?></td>
<td class="text-right"><?php echo $row['amt14']; ?></td>
</tr>
<tr>
<td><?php echo $row['item15']; ?></td>
<td class="text-center"><?php echo $row['q15']; ?></td>
<td class="text-right"><?php echo $row['amt15']; ?></td>
</tr>
<tr>
<td><?php echo $row['item16']; ?></td>
<td class="text-center"><?php echo $row['q16']; ?></td>
<td class="text-right"><?php echo $row['amt16']; ?></td>
</tr>
<tr>
<td><?php echo $row['item17']; ?></td>
<td class="text-center"><?php echo $row['q17']; ?></td>
<td class="text-right"><?php echo $row['amt17']; ?></td>
</tr>
<tr>
<td><?php echo $row['item18']; ?></td>
<td class="text-center"><?php echo $row['q18']; ?></td>
<td class="text-right"><?php echo $row['amt18']; ?></td>
</tr>
<tr>
<td><?php echo $row['item19']; ?></td>
<td class="text-center"><?php echo $row['q19']; ?></td>
<td class="text-right"><?php echo $row['amt19']; ?></td>
</tr>
<tr>
<td><?php echo $row['item20']; ?></td>
<td class="text-center"><?php echo $row['q20']; ?></td>
<td class="text-right"><?php echo $row['amt20']; ?></td>
</tr>
<tr>
<td><?php echo $row['item21']; ?></td>
<td class="text-center"><?php echo $row['q21']; ?></td>
<td class="text-right"><?php echo $row['amt21']; ?></td>
</tr>
<tr>
<td><?php echo $row['item22']; ?></td>
<td class="text-center"><?php echo $row['q22']; ?></td>
<td class="text-right"><?php echo $row['amt22']; ?></td>
</tr>
<tr>
<td class="highrow"></td>
<td class="highrow"></td>
<td class="highrow text-center"><strong>GST/Tax (%)</strong></td>
<td class="highrow text-right"><?php echo $row['taxper']; ?></td>
</tr>
<tr>
<td class="emptyrow"></td>
<td class="emptyrow"></td>
<td class="emptyrow text-center"><strong>GST/Tax Amount</strong></td>
<td class="emptyrow text-right"><?php echo $row['taxtotal']; ?></td>
</tr>
<tr>
<td class="emptyrow"></td>
<td class="emptyrow text-center"><strong>SubTotal</strong></td>
<td class="emptyrow text-right"><strong><?php echo $row['subtotal']; ?></strong></td>
</tr>
</tbody>
</table>
</div>
</div>
</div>
</div>
</div>
</div>
<?php endwhile; ?>
<script>
function myFunction() {
window.print();
}
</script>
<style>
.height {
min-height: 200px;
}
.icon {
font-size: 47px;
color: #5CB85C;
}
.iconbig {
font-size: 77px;
color: #5CB85C;
}
.table > tbody > tr > .emptyrow {
border-top: none;
}
.table > thead > tr > .emptyrow {
border-bottom: none;
}
.table > tbody > tr > .highrow {
border-top: 3px solid;
}
</style>
</div>
</body>
</html>