Detect quotes with in quotes using RegEx - php

Question

I am looking for a way to detect and drop quotes with in quotes, for example: something "something "something something" something" something.
In the above example the italic something something is wrapped in double-quotes as you can see. I want to strip the string inside from these outer quotes.
So, the expression should simply look for quotes with a text between them plus a another set of text-wrapping text, and then drop the quotes wrapping the last.
This is my current code (php):
preg_match_all('/".*(".*").*"/', $text, $matches);
if(is_array($matches[0])){
foreach($matches[0] as $match){
$text = str_replace($match, '"' . str_replace('"', '', $match) . '"', $text);
}
}

Answer 1

If the string starts with a " and the double quotes inside the string are always balanced you might use:
^"(*SKIP)(*F)|"([^"]*)"
That would match a double quote at the start of the string and then skips that match using SKIP FAIL. Then it would match ", capture in a group what is between the " and match a " again.
In the replacement you could use capturing group 1 $1
$pattern = '/^"(*SKIP)(*F)|"([^"]+)"/';
$str = "\"something \"something something\" and then \"something\" something\"";
echo preg_replace($pattern, "$1", $str);
"something something something and then something something"
Demo

Answer 2

You could leverage strpos() with the third parameter (offset) to look up all quotes and replace every quote from 1 to n-1:
<?php
$data = <<<DATA
something "something "something something" something" something
DATA;
# set up the needed variables
$needle = '"';
$lastPos = 0;
$positions = array();
# find all quotes
while (($lastPos = strpos($data, $needle, $lastPos)) !== false) {
$positions[] = $lastPos;
$lastPos = $lastPos + strlen($needle);
}
# replace them if there are more than 2
if (count($positions) > 2) {
for ($i=1;$i<count($positions)-1;$i++) {
$data[$positions[$i]] = "";
}
}
# check the result
echo $data;
?>
This yields
something "something something something something" something
You could even hide it in a class:
class unquote {
# set up the needed variables
var $data = "";
var $needle = "";
var $positions = array();
function cleanData($string="", $needle = '"') {
$this->data = $string;
$this->needle = $needle;
$this->searchPositions();
$this->replace();
return $this->data;
}
private function searchPositions() {
$lastPos = 0;
# find all quotes
while (($lastPos = strpos($this->data, $this->needle, $lastPos)) !== false) {
$this->positions[] = $lastPos;
$lastPos = $lastPos + strlen($this->needle);
}
}
private function replace() {
# replace them if there are more than 2
if (count($this->positions) > 2) {
for ($i=1;$i<count($this->positions)-1;$i++) {
$this->data[$this->positions[$i]] = "";
}
}
}
}
And call it with
$q = new unquote();
$data = $q->cleanData($data);