Question

I have a filename (or basically a string, since it doesnt need to have an extension, can have spaces though) that is encapsulated by quotes in a string of the following format:

attachment; filename="Some filename.ext"

So basically my approach (java) was to take a Matcher with a Pattern:

Matcher mat = Pattern.compile("attachment; filename=\"([\\w\\.]+)\"").matcher(filename);

But myMatcher.find() returns False

Where does the RegEx go wrong?

Answer 1

\\w does not match spaces. Also, you don’t need to (but may) escape the . inside character classes. If you just want to allow spaces, add them to the character class:

"attachment; filename=\"([\\w. ]+)\""

If there maybe more characters than spaces, letters, digits, periods and underscores, you might want to use a negative character class instead, that just takes in everything until the next quote:

"attachment; filename=\"([^\"]+)\""