WooCommerce

WooCommerce Basics

// Get product data
global $product;
$price = $product->get_price();
$name  = $product->get_name();
$stock = $product->get_stock_quantity();

// WooCommerce hooks
add_action('woocommerce_after_add_to_cart_button', 'add_custom_field');
add_filter('woocommerce_product_get_price', 'custom_price', 10, 2);

// Cart
$total = WC()->cart->get_cart_total();
WC()->cart->add_to_cart($product_id, $qty);

// Orders
$order = wc_get_order($order_id);
foreach ($order->get_items() as $item) {
    echo $item->get_name();
}

// Query products
$products = wc_get_products([
    'status' => 'publish',
    'limit'  => 20,
    'orderby'=> 'date',
]);