how can I check if a variable type is DateTime

Question

How can I check if a variable is a datetime type on php, please? I've tried this, but it seems doesn't work.

public function setRegistrationDate ($registrationDate) {

   if (!is_date($registrationDate, "dd/mm/yyyy hh:mm:ss")) {
       trigger_error('registrationDate != DateTime', E_USER_WARNING);
       return;
   }

   $this->_registrationDate = $registrationDate;
}

Answer 1

I think this way is more simple:

if (is_a($myVar, 'DateTime')) ...

This expression is true if $myVar is a PHP DateTime object.

Since PHP 5, this can be further simplified to:

if ($myVar instanceof DateTime) ...