DATE VALIDATION dd/mm/yyyy (date field with manual entry)

Is there a way to stop people filling in date fields manually?

since there is a calendar, there not only is no need for manual entry but it also avoids input error..



When I try to validate a date, it will either accept the manual date, or the calendar date but never both.



Does somebody have a solution for this? .. either to validate both the calendar date & manual entry (entered in dd/mm/yyyy)



Or

to prevent users from typing inside the date field (& use the calendar!)

(or prevent them from typing anything other than dd/mm/yyyy)



('ve tried regular expressions but it does not accept the value from the calendar)



Thanks hopefully!