以下是一个简单的PHP实例，用于实现航班查询功能，并通过表格形式展示查询结果。
```php
// 假设这是从数据库或其他数据源获取的航班数据
$flights = [
[
'flight_number' => 'CA123',
'departure_city' => '北京',
'arrival_city' => '上海',
'departure_time' => '10:00',
'arrival_time' => '12:00'
],
[
'flight_number' => 'MU456',
'departure_city' => '上海',
'arrival_city' => '广州',
'departure_time' => '13:00',
'arrival_time' => '15:00'
],
[
'flight_number' => 'CZ789',
'departure_city' => '广州',
'arrival_city' => '北京',
'departure_time' => '16:00',
'arrival_time' => '18:00'
]
];
// 查询参数
$departureCity = $_GET['departure_city'] ?? '';
$arrivalCity = $_GET['arrival_city'] ?? '';
// 过滤航班数据
$filteredFlights = array_filter($flights, function ($flight) use ($departureCity, $arrivalCity) {
return ($departureCity === '' || $flight['departure_city'] === $departureCity) &&
($arrivalCity === '' || $flight['arrival_city'] === $arrivalCity);
});
// 表格头部
echo '
