RE: [PHP] A little confusing thing on (mistakenly) geting a offset from string with multi dim index.

> -----Original Message----- > From: Rain Lee [mailto:root@3ax.org] > Sent: 15 May 2014 01:55 > To: Jim Lucas > Cc: php-general@lists.php.net > Subject: Re: [PHP] A little confusing thing on (mistakenly) geting a > offset from string with multi dim index. > > So, here is the TLDR; > > $string = 'this is a string'; > > In PHP 5.5 > isset($string['check']) === false Yes, because isset is specifically defined (nowadays) to reject string Offsets on a string. > isset($string['check'][0]) === true This is correct because the isset is only checking the final index - it's not doing any checks on 'check', so the normal PHP rules of string->integer conversion apply, and you get a zero. (If you don't know what the "normal rules" are, see http://ow.ly/wT2t0). So, $string['check'] is effectively $string[0], which is "t"; so $string['check'][0] is $string[0][0], which is set and evaluates to "t". To check that all the indexes work, you will need to do if (isset($string['check']) && isset($string['check'][0])) Or even if (isset($string['check'], $string['check'][0])) which has the same effect. Cheers! Mike -- Mike Ford, Electronic Information Developer, Libraries and Learning Innovation, 403a Leslie Silver Building, City Campus, Leeds Metropolitan University, Woodhouse Lane, LEEDS, LS1 3ES, United Kingdom E: m.ford@leedsmet.ac.uk T: +44 113 812 4730 From 22 September 2014 Leeds Metropolitan University will become Leeds Beckett University. Find out more at http://www.leedsbeckett.ac.uk To view the terms under which this email is distributed, please go to:- http://www.leedsmet.ac.uk/email-disclaimer.htm