Need Help With Regular Expression

[nackle2k10]

Hi, I'm trying to turn input from textarea into an array

here is what the textarea input look like

[input 1] [input 2] [input 3]

I'm trying to split everything inside the square bracket "[]" into an array.

here are my codes

$option = array();
$regex = "#[\[^]]*#s";
$input = "[input 1] [input 2] [input 3]";

$option = preg_split($regex, $input, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE );  

the output is

Array
(
    [0] => input 1] 
    [1] => input 2] 
    [2] => input 3]
)  

the closing bracket still there, So what am I missing in the regex pattern? Thanks

[jazzman1]

Use () to separate the regEx class.

 

Try,

$regex = "/\[(.*?)\]\s?/";

OR, 

$regex = "~\[(.*?)\]\s?~";

Edited July 28, 2013 by jazzman1

[.josh]

Near as I can tell, you're using preg_split in a funky way. Normally it's used for splitting with patterned delimiters, not for directly capturing stuff. IOW, near as I can tell, you were making the thing you wanted to match the delimiter and then using PREG_SPLIT_DELIM_CAPTURE to flip the roles of delimiter/split content, in order to effectively match for what you wanted. You can do it this way, but it's a funky ass-backwards way of doing it. Instead, when you should just be use the straightforward preg_match_all function instead.

 

This is how you would normally do it: You use preg_match_all to match for your stuff:

$option = array();
$regex = '~\[([^\]]+)\]~';
$input = "[input 1] [input 2] [input 3]";
preg_match_all($regex, $input, $matches);
$option = $matches[1];

 

If you really want to go the preg_split route, normally you would split by the delimiter, which is "] [". I threw some alternation into the mix, along with the PREG_SPLIT_NO_EMPTY flag, as a means to effectively strip the leading "[" and trailing "]" but alternatively (and perhaps ideally) you could instead trim $input first, to get rid of them, so that the preg_split pattern would only be dealing with the delimiter.

 

$option = array();
$regex = '~^\[|\]\s+\[|\]$~';
$input = "[input 1] [input 2] [input 3]";
$option = preg_split($regex, $input, -1, PREG_SPLIT_NO_EMPTY);

[nackle2k10]

@grumpy the reason why I don't use trim() to strip the "[" and "]" is the input are not handled by me, so user may use enter when inputing the option or not even use space at all. The solution I use is this pattern

$regex = "#\[|\]\s+|[\]]#s";

$input = "[input 1] [input 2] [input 3]";

$option = preg_split($regex, $input, -1, PREG_SPLIT_NO_EMPTY);

what do you guys think? Does this pattern is the best practice?

 

Btw, what happen to this forum yesterday? I tried to visit it few times and got 404 error.