Regex match a string if its in the end

Question

The following regular expression

 (cm)[\s,]

mathches

cm,
cm followed by space

how do i also make it match cm if cm is the last word in a string?

Answer 1

USe end of the line anchor.

(cm)(?:[\s,]|$)

You don't need to have a capturing group.

cm(?:[\s,]|$)

This matches cm, or cm<space> or last cm

Answer 2

cm(?=\s|$|,)

试试这个。这应该起作用。