php - How to let regex ignore everything between brackets?

Question

Consider the following string:

I have been driving to {Palm.!.Beach:100} and it . was . great!!

I use the following regex to delete all punctuation:

$string preg_replace('/[^a-zA-Z ]+/', '', $string);

This outputs:

I have been driving to PalmBeach and it  was  great!!

But I need the regex to always ignore whatever is in between { and }. So the desired output would be:

I have been driving to {Palm.!.Beach:100} and it  was  great

How can I let the regex ignore what is between { and }?

Answer 1

Try this

[^a-zA-Z {}]+(?![^{]*})

See it here on Regexr

Means match anything that is not included in the negated character class, but only if there is no closing bracket ahead without a opening before, this is done by the negative lookahead (?![^{]*}).

$string preg_replace('/[^a-zA-Z {}]+(?![^{]*})/', '', $string);