regular expression to match pipe separated strings with pipe escaping

Question

I'd like to get the single strings of a pipe-separated string, with "pipe escaping" support, e.g.:

fielda|field b |field\|with\|pipe\|inside

would get me:

array("fielda", "field b ", "field|with|pipe|inside")

How would I reach that goal with a regular expression?

Answer 1

Split  by this (?<!\\)\|

See demo.The lookbehind makes sure | is not after \.

https://regex101.com/r/pM9yO9/15

Answer 2

This should work too:

((?:[^\\|]+|\\\|?)+)

The regex will capture everything up to a single | (including \|)

DEMO

Answer 3

An other way with php, using strtr that replace \| with a placeholder:

$str = 'field a|field b|field\|with\|pipe\|inside';
$str = strtr($str, array('\|' => '#'));
$result = array_map(function ($i) {
    return strtr($i, '#', '|');
}, explode('|', $str));