Question

Is this the only way to check if an object is an instance of a class, in my case of the DateTime class?

$cls = ReflectionClass("DateTime");
if (! $cls->isInstance( (object) $var ) ) {
    // is not an instance
}

It seems a bit heavy to me.

Answer 1

You could try instanceof^­Docs…

if ($var instanceof DateTime) {
  // true
}

See also is_a^­Docs:

if (is_a($var, 'DateTime')) {
  // true
}