$re = '/(.*\/).*/';
$str = 'Folder1/Folder2/Folder3.1234/folder4.5678/ApplesandOranges.txt
Folder1/Folder2/Folder3.1234/folder4.5678/ApplesandOranges.zip?CatsAndDogs.txt
';
$subst = "\1";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
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