^(((\d{3}1-9]|\d{2}[1-9]\d|\d[1-9]\d{2}|[1-9]\d{3})(\/)(((0[13578]|1[02])(\/)(0[1-9]|[12]\d|3[01]))|((0[469]|11)(\/)(0[1-9]|[12]\d|30))|(02(\/)(0[1-9]|[1]\d|2[0-8]))))|(((\d{2})(0[48]|[2468|13579)|((048]|[2468|3579)00))(\/)02(\/)29))$ Match year/month/day, date format. E.g: 2021/08/25 [match] 2021/09/30 [match] 2018/02/28 [match] 2024/02/29 [match] 2023/02/29 [mismatch]

A proof of concept regex that captures dates and date ranges with a variety of separators. Works with both DMY and MDY, and if one is not needed, it can be easily deleted from the regex. The full variety of months needs to be implemented by the programmer themselves since developing it in regex101 is unfeasible and would clutter the regex.

Here's a regular expression to handle a specific year in the different forms of dates: YYYY-MM-DD DD-MM-YYYY MM-DD-YYYY

This is still a working in progress Need to do Unit Tests and search for more use cases Match partial cases of 8601 such as: missing offset missing time only date and offset nano present or not (and being from 1 digit to 9 digits) Also properly captures the data by capturing only: year, month, date, hour, minute, second, nano and offset (be it 'Z' or '+02:00' or' +0200')

Covering Dates starting from year 2009 and older in French and English Some of the valid Dates format April 2nd 2008 April 2 2008 April 02 2008 2009-01-01 31-03-2009 03-31-2009 31 March 2009 March 31 2009 31 mars 2009 May 10th 1989 April 2nd 2008 2009.01.01 2009 1 31 31st december 2009 31 décembre 2009 31 Decembre 2009 2009/02/01 2009.01.01 2009 01 01 31 03 2009 12 31 2009

Valid date (DD-MM-YYYY) from 1900 to 2099

Date format dd.mm.yyyy

file_(name)|file_(path)|file_(size)|file_(date) - searching (regex rule) file_info, name, path, size, date - keeping (result)