为了在 PHP 配置中使用 FTP 函数，应该在安装 PHP 时添加 --enable-ftp 选项。
在 Windows 上，此扩展始终编译为共享扩展，因此必须在 php.ini 中启用。
For some reason folks downvoted the previous entry for this, BUT... indeed, as of PHP 7, to enable this on Windows you have to add the line:
extension=php_ftp.dll
to your php.ini to resolve PHP errors that tell you PHP FTP functions are not defined; the line isn't in there (where, many things are and are just commented out).On linux, one would enable ftp on their php7 server by uncommenting or adding the line "extension=ftp.so" in their php.ini file (likely at /etc/php/php.ini, unless the user moved it).If you are using PHP 7 under Windows you have to enable ftp in php.ini with extension=php_ftp.dll.