Regex matches all sets except certain

Question

I am sure that this was asked earlier, but I cannot find it (or I know the correct wording for the search)

Basically I want a regular expression that matches all non-alphanumeric except hyphens. So basically match \ W + except exclude '-' I'm not sure how to exclude certain from the finished set.

Answer 1

\W is short for [^\w] . So:

 [^\w-]+ 

A bit of background:

• […] defines the set
• [^…] cancels the set
• As a rule, each \v (smallcase) set is negated by the symbol \v (in upper case), where V is any letter that defines the set.
• for international characters, you can see [[:alpha:]] and [[:alnum:]]

Answer 2

 [^\w-]+ 

will do just that. Match any non- \w characters except for a hyphen.

Answer 3

You can use:

 [^a-zA-Z0-9_-] 

or

 [^\w-] 

to match a single non-hyphen, not an alphanumeric. To match one or more prefix with +

Answer 4

In Java7 or later, you need to add (?U) to match all language characters. eg.

 (?U)[^\w-] 

In the Java string (you need to print the \ character with another):

 (?U)[^\\w-]