Checking session array for value (PHP in_array) - php

Question

My simple shopping cart stores products id's in a session array.
I'm trying to set up an if/else statement to enable/disable my "Add to cart" button based on the product ID being in array or not.
<?php
session_start();
//Show cart array
print_r($_SESSION['cart']);
echo '<br><br>';
//Return "yes" or "no"
$panier = $_SESSION['cart'];
$produit = "5";
if (in_array($produit, $panier)) {
print "yes man!";
}
else {
print "no man!";
}
?>
I'm making sure 5 is part of the array values by displaying them of this test page, but the second part always returns "no man!"
looks simple enough to me. What am i doing wrong ?
print_r command output is
5,5
no man!
that is because i've added 2 of the "5" product id to my cart
If I change this line
print_r($_SESSION['cart']);
for
print_r($_SESSION);
I get
Array ( [cart] => 5,3,3,3,3,3,3,3,2 )
no man!

Answer 1

So, according to you, $_SESSION['cart'] = "5,5"; and it means it is a string. So the right code to look up your value is strpos():
$pos = strpos($produit, $_SESSION['cart']);
if($pos !== false) {
echo "YES";
}
else {
echo "NO";
}
BUT there's a huge risk to get the wrong answer for this. Imagine, you have two products in your cart - first with id 15 and the other with id 7. You'll be looking for id 5. What would the above code output? It will output "YES".
So, instead of using a string, I suggest you use multidimensional array (if you want to stick with sessions). In this particular case then, the variable $_SESSION["cart"] would be an array and with adding new products it would look like this:
$_SESSION["cart"] = array(); // initial value, don't call it every time or it'll flush your array
$_SESSION["cart"][] = $product_ID;
Or similar to it.
print_r will give you a similarly-looking output:
Array(
cart => array(
[0] => 5
[1] => 17
[2] => 5
)
)
Then, in_array should work. But, plan your storing wisely ;)

Answer 2

As jon asked it is better put always the output of your program But for now I am suspecting your problem is in the in_array check this link A problem about in_array it might help