wordpress上传图片按时间重命名

在wp-content/theme/主题名/functions.php末尾加如下代码

add_filter('wp_handle_upload_prefilter', 'custom_upload_filter' );function custom_upload_filter( $file ){    $info = pathinfo($file['name']);    $ext = $info['extension'];    $filedate = date('YmdHis').rand(10,99);//为了避免时间重复，再加一段2位的随机数    $file['name'] = $filedate.'.'.$ext;    return $file;}