Regex to validate date format dd/mm/yyyy

Question

I need to validate a date string for the format dd/mm/yyyy with a regular expresssion.

This regex validates dd/mm/yyyy, but not the invalid

Answer 1

Another answer which validates day (dd) depending upon the month (mm) and the year (yyyy) (i.e., also validates 29th Feb in leap years) and allows years ranging from 0001 to 9999 (0000 in a invalid year according to the Gregorian calendar)

^(?:(?:(?:0[1-9]|[12]\d|3[01])/(?:0[13578]|1[02])|(?:0[1-9]|[12]\d|30)/(?:0[469]|11)|(?:0[1-9]|1\d|2[0-8])/02)/(?!0000)\d{4}|(?:(?:0[1-9]|[12]\d)/02/(?:(?!0000)(?:[02468][048]|[13579][26])00|(?!..00)\d{2}(?:[02468][048]|[13579][26]))))$