Hide a specific Woocommerce products from loop if they are in cart

Question

I'm trying to write a hook that hides a specific product from the shop page if it's in the cart, but I can't seem to figure out two things.

function find_product_in_cart() {

    $hide_if_in_cart = array(6121, 6107, 14202, 14203);
    $in_cart = false;

    foreach( WC()->cart->get_cart() as $cart_item ) {

        $product_in_cart = $cart_item['product_id'];

        foreach ( $hide_if_in_cart as $key => $value ) {
            if ( $product_in_cart === $value ) {
                $in_cart = true;
            }
        }

        if ( $in_cart ) {
            echo 'Product in cart';
        } else {
            echo 'Not in cart!';
        }

    }
}
add_action('woocommerce_before_shop_loop_item', 'find_product_in_cart

1. The code prints out "Product in cart" everywhere, because one product with ID '14202' is in the cart. My logic is wrong somewhere...
2. I don't know how to hide a single product, right now I print a line of text, but I want to be able to either display: none; it or maybe use a specific function that hides product in certain scenario's.

This is the output at the moment: https://i.gyazo.com/d85bd93598ada7aa96bee9a1d7393c3c.png

Answer 1

The following code will remove a specific defined products from Woocommerce shop and archive pages when they are in cart, using this dedicated Woocommerce action hook:

add_action( 'woocommerce_product_query', 'hide_specific_products_from_shop', 20, 2 );
function hide_specific_products_from_shop( $q, $query ) {
    if( is_admin() && WC()->cart->is_empty() )
        return;

    // HERE Set the product IDs in the array
    $targeted_ids = array( 6121, 6107, 14202, 14203 );

    $products_in_cart = array();

    // Loop through cart items
    foreach( WC()->cart->get_cart() as $cart_item ){
        if( in_array( $cart_item['product_id'], $targeted_ids ) ){
            // When any defined product is found we add it to an array
            $products_in_cart[] = $cart_item['product_id'];
        }
    }
    // We remove the matched products from woocommerce lopp
    if( count( $products_in_cart ) > 0){
        $q->set( 'post__not_in', $products_in_cart );
    }
}

Code goes in function.php file of your active child theme (or active theme). Tested and works.