'Does accessing a false Boolean value in $_POST return false or null?

I am sending x = false; Boolean value through the POST method. Will Request::post['x'] or $_POST['x'] return Boolean false or null?

If I try (!isset($_POST['x'])) it gives me true, but I don't understand why.

php


Solution 1:[1]

Note that using ! (the NOT logical operator), means that (!isset($_POST['x'] )) will return true if x is not set (i.e. null).

All data in $_POST is untyped; it is all a string. If you need to send Boolean values, one option would be to compare a string to "true" or "false".

if ($_POST['x'] === "true") {
    // True
} elseif ($_POST['x'] === "false") {
    // False
} else {
    // Error - not equal to true or false string
}

A note regarding comparison operators in PHP:

$x == $y returns true if $x is equal to $y

$x === $y returns true if $x is equal to $y and they are of the same type

Solution 2:[2]

If $_POST['x'] will contain anything, except null, then isset() will return true.

Sources

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Source: Stack Overflow

Solution Source
Solution 1 Chris
Solution 2 zen

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