$re = '/^three-dxf-master\/[^\/]*\/?$/m';
$str = 'three-dxf-master/
three-dxf-master/.DS_Store
three-dxf-master/.gitignore
three-dxf-master/LICENSE
three-dxf-master/README.md
three-dxf-master/bower.json
three-dxf-master/bower_components/
three-dxf-master/bower_components/foo
three-dxf-master/bower_components/bar/
www/
www/xxx
www/yyy/
www/yyy/zzz';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php