Regex Letters, Numbers, Dashes, and Underscores

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 also开发者_Python百科 like to match on dashes and underscores in the same expression. Anyone know how?

I would like to be able to match product_name and product-name

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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\-\_]+)

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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_-]+)

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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.

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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)