Verify start time is earlier than end time

This?

https://xlinesoft.com/phprunner/docs/check_if_start_date_is_earlier_than_end_date.htm

Unfortunately I cannot use this code because I want to check when adding a record to a page with two entry fields: from and to ...

This exactly what this code does. I guess you need to elaborate why wouldn't it work for you.

works great now !
Thanks