Show hide custom Woocommerce checkout field based on selected payment method

Question

Hi I added custom field in billing form using this code below.

add_filter('woocommerce_billing_fields', 'custom_woocommerce_billing_fields');

function custom_woocommerce_billing_fields($fields)
{

    $fields['billing_options'] = array(
        'label' => __('If you pay by Invoice. Please add Your Invoice Number Here ', 'woocommerce'), // Add custom field label
        'placeholder' => _x('Invoice Number', 'placeholder', 'woocommerce'), // Add custom field placeholder
        'required' => false, // if field is required or not
        'clear' => false, // add clear or not
        'type' => 'text', // add field type
        'class' => array('my-css')    // add class name
    );

    return $fields;
}

I have two payment options 1. Cash on delivery 2.Realex Payments HPP – Credit Card.

Is it possible to show custom field only then 1. Cash on delivery selected as payment option.?

Thank you

Answer 1

The following code will hide billing_options custom optional checkout field when the selected payment method is Cash on delivery ("cod"):

// Conditional Show hide checkout fields based on chosen payment methods
add_action( 'wp_footer', 'conditionally_show_hide_billing_custom_field' );
function conditionally_show_hide_billing_custom_field(){
    // Only on checkout page
     if ( is_checkout() && ! is_wc_endpoint_url() ) :
    ?>
    <script>
        jQuery(function($){
            var a = 'input[name="payment_method"]',
                b = a + ':checked',
                c = '#billing_options_field'; // The checkout field <p> container selector

            // Function that shows or hide checkout fields
            function showHide( selector = '', action = 'show' ){
                if( action == 'show' )
                    $(selector).show( 200, function(){
                        $(this).addClass("validate-required");
                    });
                else
                    $(selector).hide( 200, function(){
                        $(this).removeClass("validate-required");
                    });
                $(selector).removeClass("woocommerce-validated");
                $(selector).removeClass("woocommerce-invalid woocommerce-invalid-required-field");
            }

            // Initialising: Hide if choosen payment method is "cod"
            if( $(b).val() !== 'cod' )
                showHide( c, 'hide' );
            else
                showHide( c );

            // Live event (When payment method is changed): Show or Hide based on "cod"
            $( 'form.checkout' ).on( 'change', a, function() {
                if( $(b).val() !== 'cod' )
                    showHide( c, 'hide' );
                else
                    showHide( c );
            });
        });
    </script>
    <?php
    endif;
}

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