以下是一个简单的PHP单据打印实例，我们将创建一个包含订单信息的单据，并使用HTML和PHP将其打印出来。
```php
// 假设从数据库或其他来源获取订单信息
$orders = [
[
'order_id' => 1,
'customer_name' => '张三',
'order_date' => '2021-10-01',
'items' => [
['item_id' => 101, 'item_name' => '苹果', 'quantity' => 5, 'price' => 2.5],
['item_id' => 102, 'item_name' => '香蕉', 'quantity' => 3, 'price' => 1.5]
],
'total_price' => 16.5
],
[
'order_id' => 2,
'customer_name' => '李四',
'order_date' => '2021-10-02',
'items' => [
['item_id' => 103, 'item_name' => '橙子', 'quantity' => 2, 'price' => 3.0],
['item_id' => 104, 'item_name' => '梨', 'quantity' => 4, 'price' => 1.8]
],
'total_price' => 9.2
]
];
// 单据打印函数
function printInvoice($orders) {
echo "
