Add custom Checkout field based on Cart weight in Woocommerce

Question

On the checkout page, I would like to add a custom field if the contents of the cart weighs over 1000kg.

Is there a way of adding an if statement (to form-checkout.php?) which gets the cart weight and then I can add in a select field?

Answer 1

First read the official related documentation to customize checkout fields or this documentation too.

Here is an example that will add a custom billing select field when cart weight is over 1000 Kg (1 Ton) in checkout page:

add_filter( 'woocommerce_checkout_fields' , 'customizing_checkout_fields', 10, 1 );
function customizing_checkout_fields( $fields ) {

    if( WC()->cart->get_cart_contents_weight() > 1000 ) {

        // Custom Select field
        $fields['billing']['billing_custom'] = array(
            'type'     => 'select',
            'label'    => __("Cart weight over 1 Ton", "woocommerce"),
            'class'    => array('form-row-wide'),
            'options'  => array(
                ''         => __("Choose an option please…", "woocommerce"),
                'option-1' => __("Option 1", "woocommerce"),
                'option-2' => __("Option 1", "woocommerce"),
                'option-3' => __("Option 1", "woocommerce"),
            ),
            'priority' => '120',
            'required' => true,
        );
    }

    return $fields;
}

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