Yii2 comes empty instead of false?

Question

PHP

I send JSON (POST):

{
  "id": 1,
  "param": false
}

Output:
print_r(Yii::$app->request->post());
I get an empty param :

Array
(
    [id] => 1
    [param] => 
)

And it needs to be like this:

Array
(
    [id] => 1
    [param] => false
)

Answer 1

print_r does not display false and null. Use var_dump.
upd: or rather, at the time of display, print_r does __toString for each element. And for false __toString returns an empty string. Therefore, it is not displayed.