val.replace(/[^a-zA-Z_-0-9]/g, '') produce SyntaxError: invalid range in character class

Question

I need to replace all chars which are not match with range a-zA-Z_-0-9. So I do val.replace(/[^a-zA-Z_-0-9]/g, '') but get error. How can I bit this? Thanks

Answer 1

If you want to include the minus sign "-" in the character class, you have to put it into the end of range:

val.replace(/[^a-zA-Z_0-9-]/g, '')

Answer 2

You expect that - character to be parsed as being literal, but it is in fact parsed as a range: _-0 means _ to 0, just like a-z means a to z. However, since _ has a higher character code than 0, you get an error.

In your case, just escape it: \-. This is parsed as the - character.

Answer 3

I would prefer this regex:

val.replace(/[^\w-]+/gi, "");