用逗号分隔，而不是（和）

i've problem by using the preg_split method. I wanna split by comma but only if the comma isn't between ( and ).

For example:

id,user(id,firstname),image(id)

Should return:

0 => id
1 => user(id,firstname)
2 => image(id)

I have solved this issue using preg_split with PREG_SPLIT_DELIM_CAPTURE.

$tokens = preg_split('#(\,|\(|\))#', 'id,user(id,firstname),image(id)', PREG_SPLIT_DELIM_CAPTURE);

Returns:

["id", ",", "user", "(", "id", "firstname", ")", "image", "(", "id", ")"]

After that you can parse that array with a simple switch case.

You may want to try a parser-generator rather than a regex. I'm not familiar with the alternatives in PHP, but this answer indicates a couple alternatives.

I would suggest trying to find a parser instead, but it can be done using regular expressions.

Use the following regular expression: /\G(?> *)(?|([^,]*\((?>\\.|[^()])+\)[^,]*)|(?![()])([^,]+?)) *(?:,|$)/g

More details here: http://regex101.com/r/nA7dW5

Good luck

The regex /(\([^()]+\))|([^,]+)/ will match everything, except the commas outside parentheses. Does it helps?

Quick and readable solution might be this:

<?php
function parse($str) {
    $str = preg_replace('~(\(.*?),(.*?\))~', '$1_#_PLACEHOLDER_#_$2', $str);

    $items = array();
    foreach (explode(',', $str) as $item) {
        $items[] = str_replace('_#_PLACEHOLDER_#_', ',', $item);
    };
    return $items;
}

var_dump(parse('id,user(id,firstname),image(id)'));

It could definitely be done with a single regex, but readability would be severely hurt.