Regex to remove non alphanumeric characters from UTF8 strings

Question

How can I remove characters, like punctuation, commas, dashes etc from a string, in a multibyte safe manner?

I will be working with input from many different languag

Answer 1

There are the unicode character class thingys that you can use:

• http://www.regular-expressions.info/unicode.html
• http://php.net/manual/en/regexp.reference.unicode.php

To match any non-letter symbols you can just use \PL+, the negation of \p{L}. To not remove spaces, use a charclass like [^\pL\s]+. Or really just remove punctuation with \pP+

Well, and obviously don't forget the regex /u modifier.