Question

What is best practice to select content between a pair of delimiter using regular expression excluding the delimiters in PHP and JS?

aassssd [dddd] fff ffff (delimiter=[..])   output -> dddd
aassssd QddddQ fff ffff (delimiter=Q)      output -> dddd
aassssd RddddQ fff ffff (delimiters=R...Q) output -> dddd
aassssd "dddd" fff ffff (delimiter=")      output -> dddd

Concern is about excluding delimiters, selecting whole is relatively easy:

/\"[^"]\"/ //for  line four

It’s preferable that solution return a scaler. An ideal answer only uses RegEx, that can be tested in http://regexpal.com/

Answer 1

aassssd [dddd] fff ffff (delimiter=[..])   output -> dddd

RegEx for PHP:

(?<=\[).*?(?=\])

RegEx for JS (works in PHP too):

[^\[]*?(?=\])