Regex Match decimal number between 0 to 1

问题

I want to match a decimal number between 0 and 1 (inclusive), but the regex I wrote will match anything more than 1 too: https://regex101.com/r/mN1iT5/3

How can I solve this

^[0-1]{1}(\.[0-9]{1,2})?$

回答1:

Do:

^(?:0*(?:\.\d+)?|1(\.0*)?)$

• 0*(?:\.\d+)? matches any number of 0 followed by one or digits

• 1(\.0*)? matches 1 followed by a decimal point, and any number of 0s

• The above two are | (OR-ed) to match any one of them

Demo

来源：https://stackoverflow.com/questions/40457957/regex-match-decimal-number-between-0-to-1