Validate that input Date is before than current date

Hi! im making the web development course and i need to validate the dateofbirth input is before than the actual date, but i try and i can't get it. How you do that? thanks in advance. :)


My bad i already did it,

i use 

SyntaxEditor Code Snippet

PersonForm.Record.Person.DateOfBirth >= CurrDate() 

i was just making complicated things. Thanks