What's a good regex to include accented characters in a simple way?

Question

Right now my regex is something like this:

[a-zA-Z0-9] but it does not include accented characters like I would want to. I would also like - \' , to be included.

Answer 1

Accented Characters: DIY Character Range Subtraction

If your regex engine allows it (and many will), this will work:

(?i)^(?:(?![×Þß÷þø])[-'0-9a-zÀ-ÿ])+$

Please see the demo (you can add characters to test).

Explanation

• (?i) sets case-insensitive mode
• The ^ anchor asserts that we are at the beginning of the string
• (?:(?![×Þß÷þø])[-'0-9a-zÀ-ÿ]) matches one character...
• The lookahead (?![×Þß÷þø]) asserts that the char is not one of those in the brackets
• [-'0-9a-zÀ-ÿ] allows dash, apostrophe, digits, letters, and chars in a wide accented range, from which we need to subtract
• The + matches that one or more times
• The $ anchor asserts that we are at the end of the string

Reference

Extended ASCII Table