- var_dump: documentation ( source)
- array_keys: documentation ( source)
- array_diff: documentation ( source)
<?php
$keys = array('name', 'type', 'tmp_name', 'error', 'size');
$fileArr = array('name');
$fileKeys = array_keys($fileArr);
var_dump(empty( array_diff( $fileKeys, $keys) ));