问题
My question is simple suppose I would like to match the vowels in a word, but I would like to match them in a specific order as the appear such as a, e, i, o, u. How would I go about doing this?
回答1:
So you're looking for a followed by some characters, then e followed by some characters, and so forth?
In other words, a followed by stuff that isn't e, then e. Then stuff that isn't i then i. Then stuff that isn't o then o. And finally stuff that isn't u and lastly a u.
In regexp terms, that's a[^e]*e[^i]*i[^o]*o[^u]*u
(You could get by with a .*? but why do that when you can more precisely define what you mean.)
回答2:
I would go with:
a.*?e.*?i.*?o.*?u
But this has the same problem that is pointed out in a comment by Alvin to Votley's answer. This is due to the question not specified enough. It is not specified what the priority is.
回答3:
You mean in alphabetical order?
You can't do that with a single regex unfortunately. Instead use one regex for each vowel.
来源：https://stackoverflow.com/questions/6066799/regex-match-ordering