When using PHP, I find myself writing code like this a lot:
$target = $_SESSION[AFTER_LOGIN_TARGET];
unset($_SESSION[AFTER_LOGIN_TARGET]);
return $target;
In Python, there is a dict.pop method that would let me do something similar in one statement, without a temporary variable:
return session.pop(AFTER_LOGIN_TARGET)
Is there a similar function or trick in PHP?
I don't see a built-in function for this, but you can easily create your own.
/**
* Removes an item from the array and returns its value.
*
* @param array $arr The input array
* @param $key The key pointing to the desired value
* @return The value mapped to $key or null if none
*/
function array_remove(array &$arr, $key) {
if (array_key_exists($key, $arr)) {
$val = $arr[$key];
unset($arr[$key]);
return $val;
}
return null;
}
You can use it with any array, e.g. $_SESSION:
return array_remove($_SESSION, 'AFTER_LOGIN_TARGET');
Short and Sweet
With PHP 7+ you can use the null coalescing operator to shorten this function greatly. You don't even need isset()!
function array_remove(array &$arr, $key) {
$val = $arr[$key] ?? null;
unset($arr[$key]);
return $val;
}
isset will return false if the value is null, causing the function to leave the entry in the array.
array_key_exists. isset would suffice.php -r '$x["foo"] = null; var_dump(isset($x["foo"]));' outputs bool(false). array_key_exists is slightly slower, but it returns true even if the key is mapped to null.
I think what you are looking for is array_slice()
$target = array_slice(
$_SESSION,
array_search('AFTER_LOGIN_TARGET', $_SESSION),
1
);
Variant of this answer, using null coalesce.
function array_remove(array &$arr, $key) {
$value = $arr[$key] ?? null;
unset($arr[$key]);
return $value;
}
Why about a helper function? Something like that:
function getAndRemoveFromSession ($varName) {
$var = $_SESSION[$varName];
unset($_SESSION[$varName]);
return $var;
}
So if you call
$myVar = getAndRemoveFromSession ("AFTER_LOGIN_TARGET");
you have what you asked for (try it a little, I haven't used php for many times :-])
dict.pop()function does, and is useless in the described case