Will this work?

Will this => ^[A-Za-z0-9 -]*$ work to match and number and combnation of letters, numbers, spaces, and a dash?

Nearly - you need to put the "-" as the first character in the square brackets, otherwise it will complain that you have an unterminated range starting from space. i.e.
^[-A-Za-z0-9 ]*$

It will also match an empty string, which may or may not be what you want. If you want it to match at least one character then replace the * with +.

Dave

No, the hyphen is not "seen" as a range character when placed at the start and end of a character class.