ftp_cdup can only up to the parent and if you want test a directory that is not a child then you can't with ftp_cdup ;)
PHP - Manual: ftp_cdup
2024-12-21
(PHP 4, PHP 5, PHP 7, PHP 8)
ftp_cdup — 切换到当前目录的父目录
$ftp_stream
): bool切换目录至当前目录的父目录 (上级目录)。
ftp_stream
FTP 连接的标识符。
成功时返回 true
, 或者在失败时返回 false
。
示例 #1 ftp_cdup() 例子
<?php
// set up basic connection
$conn_id = ftp_connect($ftp_server);
// login with username and password
$login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass);
// change the current directory to html
ftp_chdir($conn_id, 'html');
echo ftp_pwd($conn_id); // /html
// return to the parent directory
if (ftp_cdup($conn_id)) {
echo "cdup successful\n";
} else {
echo "cdup not successful\n";
}
echo ftp_pwd($conn_id); // /
ftp_close($conn_id);
?>
ftp_cdup can only up to the parent and if you want test a directory that is not a child then you can't with ftp_cdup ;)