我编写了检查文件是否存在的函数.如果文件系统中没有这样的文件，则返回false，否则返回true.我的函数检查(自下而上)目录结构.应该相当确定 $root 目录存在.

I wrote function which check if file can exists. It return false if there is no such file in filesystem, otherwise it returns true. My function checks (bottom-up) directory structure. One should be fairly sure that $root directory exists.

private function fileCanExists($root, $path) {
    $root .= '/';
    if (file_exists($root . $path))
        return true;
    while ($path != '.') {
        $path = dirname($path);
        if (file_exists($root . $path)) {
            if (is_readable($root . $path))
                return false;
            else
                return true;
        }
    }
    return false;
}

这就是我写的意思:

我想检查文件是否不存在.

I want to check if file do not exists.