tp5 下载.apk包文件

function load(){
    $file = '../file/aa.apk';
	if (file_exists($file)) {
		header('Content-Description: File Transfer');
		header('Content-Type: application/vnd.android.package-archive');
		header('Content-Disposition: attachment; filename=' . basename($file));
		header('Content-Transfer-Encoding: binary');
		header('Expires: 0');
		header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
		header('Pragma: public');
		header('Content-Length: ' . filesize($file));
		ob_clean();
		flush();
		readfile($file);
		exit;
	} else {
		return false;
	}
}