无论字符序列如何，如何创建匹配的正则表达式？

Question

Say I am requiring a user to input the certain words provided and he/will just input it on a textbox which will be validated regardless of order.I have been looking for answers for hours and I'm stuck :/

e.g. the words should be inputted are: foo, bar, green.

and I can still match it even if the order is bar green foo or green foo bar

I pretty much know the very basics of regex but I don't know how to match with this type of condition.. Any answers will be much appreciated!

Answer 1

This checks if you have exactly these three words in the input and nothing more:

/^(?=.*\bbar\b)(?=.*\bgreen\b)(?=.*\bfoo\b)(?:\s*\b\w+\b\s*){3}$/s