regex - Regular Expression all characters except last one

Question

This is my string: 50.00.00..00.00

I want to match all . except the last one, so after a replace I end up with 50000000.00

Can somebody help me with this?

Answer 1

.(?=.*.)

Matches a dot (.), which there must be another dot following it ((?=.*.)).

(This assumes the regex engine supports lookahead, e.g. PCRE, Python, etc.)