Regular expression for date times

can anyone tell me what will be the regular expression of开发者_如何学Go the following:

yyyy-mm-dd(space)hr:i:s 

e.g., exactly this format:

2001-07-31 22:05:00

I have to put this reg expression in ‘regex’

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Depending on the regex library:

\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}

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(\d{4})-(\d{2})-(\d{2})\s+(\d{2}):(\d{2}):(\d{2})

Parenthesis are if you want to catch the values of year, month etc.

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Something like this:

[12][0-9]{3}-[01][0-9]-[0-3][0-9]\s[0-2][0-9]:[0-5][0-9]:[0-5][0-9]

(with some very basic validation for invalid input like 9999-99-99 99:99:99)

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matches a date in yyyy-mm-dd format from between 1900-01-01 and 2099-12-31

^(19|20)\d\d[- /.](0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])$