Storing Arrays in PHP Sessions

Let's consider the code we made in the previous lesson:

<?php
	if (!empty($_GET)) {
		$_SESSION['num1'] = $_GET['num1'];
		$_SESSION['num2'] = $_GET['num2'];
	}
?>

Actually, we could take and write all form data at once into $_SESSION:

<?php
	if (!empty($_GET)) {
		$_SESSION = $_GET;
	}
?>

And in the file test2.php do this:

<?php
	if (!empty($_SESSION)) {
		echo array_sum($_SESSION);
	}
?>

The advantage of this approach is that our code will work regardless of the number of inputs in the form.

However, there is also a drawback: by overwriting $_SESSION we erase all data that was previously there. Who knows what another script of ours wrote there? And we will delete it.

Let's do it differently:

<?php
	if (!empty($_GET)) {
		$_SESSION['nums'] = $_GET;
	}
?>

As you can see, we wrote not just one value into the session variable, but an entire array. Now in the file test2.php we can find the sum of the elements of this array:

<?php
	if (!empty($_SESSION)) {
		echo array_sum($_SESSION['nums']);
	}
?>

On one page, using a form, ask the user for their name, age, salary, and something else. Store this data in one session variable in the form of an array. When accessing another page, iterate through the saved data with a loop and display each element of the array in its own li tag of the ul tag.