Regex Letters, Numbers, Dashes, and Underscores

Question

Im not sure how I can achieve this match expression. Currently I am using,

([A-Za-z0-9-]+)

...which matches letters and numbers. I would

Answer 1

Your expression should already match dashes, because the final - will not be interpreted as a range operator (since the range has no end). To add underscores as well, try:

([A-Za-z0-9_-]+)

Answer 2

Just escape the dashes to prevent them from being interpreted (I don't think underscore needs escaping, but it can't hurt). You don't say which regex you are using.

([A-Za-z0-9\-\_]+)

Answer 3

Depending on your regex variant, you might be able to do simply this:

([\w-]+)

Also, you probably don't need the parentheses unless this is part of a larger expression.

Answer 4

You can indeed match all those characters, but it's safer to escape the - so that it is clear that it be taken literally.

If you are using a POSIX variant you can opt to use:

([[:alnum:]\-_]+)

But a since you are including the underscore I would simply use:

([\w\-]+)

(works in all variants)