Adding multiple items to WooCommerce cart at once

Question

I have 3 IDs of the different items that I want to add to my shopping cart. I could use https://url.com/shop/cart/?add-to-cart=3001 but when I want to add 3 items I can't do it. Is there any function/script I can add to add this ability to my shopping website?

I tried to add an & after the add-to-cart and tried to add a new value but GETs get overridden right?: https://url.com/shop/cart/?add-to-cart=3001&add-to-cart=2002&add-to-cart=1001

Answer 1

I found the answer!

Simply add the following script to your theme's functions.php:

function woocommerce_maybe_add_multiple_products_to_cart() {
// Make sure WC is installed, and add-to-cart qauery arg exists, and contains at least one comma.
if ( ! class_exists( 'WC_Form_Handler' ) || empty( $_REQUEST['add-to-cart'] ) || false === strpos( $_REQUEST['add-to-cart'], ',' ) ) {
    return;
}

// Remove WooCommerce's hook, as it's useless (doesn't handle multiple products).
remove_action( 'wp_loaded', array( 'WC_Form_Handler', 'add_to_cart_action' ), 20 );

$product_ids = explode( ',', $_REQUEST['add-to-cart'] );
$count       = count( $product_ids );
$number      = 0;

foreach ( $product_ids as $product_id ) {
    if ( ++$number === $count ) {
        // Ok, final item, let's send it back to woocommerce's add_to_cart_action method for handling.
        $_REQUEST['add-to-cart'] = $product_id;

        return WC_Form_Handler::add_to_cart_action();
    }

    $product_id        = apply_filters( 'woocommerce_add_to_cart_product_id', absint( $product_id ) );
    $was_added_to_cart = false;
    $adding_to_cart    = wc_get_product( $product_id );

    if ( ! $adding_to_cart ) {
        continue;
    }

    $add_to_cart_handler = apply_filters( 'woocommerce_add_to_cart_handler', $adding_to_cart->product_type, $adding_to_cart );

    /*
     * Sorry.. if you want non-simple products, you're on your own.
     *
     * Related: WooCommerce has set the following methods as private:
     * WC_Form_Handler::add_to_cart_handler_variable(),
     * WC_Form_Handler::add_to_cart_handler_grouped(),
     * WC_Form_Handler::add_to_cart_handler_simple()
     *
     * Why you gotta be like that WooCommerce?
     */
    if ( 'simple' !== $add_to_cart_handler ) {
        continue;
    }

    // For now, quantity applies to all products.. This could be changed easily enough, but I didn't need this feature.
    $quantity          = empty( $_REQUEST['quantity'] ) ? 1 : wc_stock_amount( $_REQUEST['quantity'] );
    $passed_validation = apply_filters( 'woocommerce_add_to_cart_validation', true, $product_id, $quantity );

    if ( $passed_validation && false !== WC()->cart->add_to_cart( $product_id, $quantity ) ) {
        wc_add_to_cart_message( array( $product_id => $quantity ), true );
    }
}
}

 // Fire before the WC_Form_Handler::add_to_cart_action callback.
 add_action( 'wp_loaded',        'woocommerce_maybe_add_multiple_products_to_cart', 15 );

And then you can simply use http://shop.com/shop/cart/?add-to-cart=3001,3282 to add multiple items at once. Put a comma between different IDs.

Thanks to dsgnwrks for the solution.