官方文档 https://www.php.net/manual/zh/pdostatement.bindparam.php
注意: bindParam 第2个参数 mixed &$variable 是引用传值
<?php
foreach ($params as $key => &$val) {
$sth->bindParam($key, $val);
}
?>
<?php
foreach ($params as $key => $val) {
$sth->bindParam($key, $val);
}