why does filter_input() return NULL when I manually assign value to $_POST array?
filter, php, validation
Solution
`filter_input()` doesn't read from the _POST/_GET/_COOKIE/_SERVER/_ENV superglobal arrays. It reads from the original sources of those values respectively (which are also used to populate the superglobals).
Problem
I'm following some exercises about data validation and decided to mess around with the `filter_input()` function. When I try to run this code: ``` $_POST['var'] = 10; $filtered = filter_input(INPUT_POST, 'var', FILTER_VALIDATE_FLOAT); var_dump($filtered); ``` `var_dump($filtered)` returns NULL. I know the code works if `$_POST['var']` is assigned a value by submitting a form, but I'm just wondering why manually assigning a value to the `$_POST[]` array doesn't return `float(10)`?