Java字符串的正则表达式包含包含字母和：/

Question

I have a set of Strings like "04/21 01:55 P " , "1" , "10/21" . I wrote a regex as follows

^([[0-9]{2}/[0-9]{2} [0-9]{2}:[0-9]{2} P|A ]+)

It should accept only the format of Strings like "04/21 01:55 P " . But it is also accepting strings like "1" , "10/21"

Could any one let me know where I want wrong.

Answer 1

Replace the surrounding [] by () .

You'll need to change the P|A part too, either by (P|A) or [PA] .

Answer 2

You've put everything in one big character class, which is why single digits are being matched as well. You can try something like

^(\d{2}/\d{2} \d{2}:\d{2} (?:P|A) )+