我正在制作日历系统,并不断出现此错误,但不知道如何解决。
致命错误:未捕获错误:在A:\ xampp \ htdocs \ practice \ index.php:5堆栈中的bool上调用成员函数bind_param():5堆栈跟踪:#0 A:\ xampp \ htdocs \ practice \ index。 php(267):build_calendar(7,2020)#1 {main}在第5行的A:\ xampp \ htdocs \ practice \ index.php中抛出
<?php
function build_calendar($month, $year) {
$mysqli = new mysqli('localhost', 'root', '', 'bookingcalendar');
$stmt = $mysqli->prepare("select * from bookings where MONTH(date) = ? AND YEAR(date) = ?");
$stmt->bind_param('ss', $month, $year);
$bookings = array();
if ($stmt->execute()) {
$result = $stmt->get_result();
if ($result->num_rows > 0) {
while ($row = $result->fetch_assoc()) {
$bookings[] = $row['date'];
}
$stmt->close();
}
}
}