WooCommerce Custom Checkout Fields with Fields Added in Order Email

woo-custom-checkout-fields-with-email.php

<?php
/* Add the field to the checkout */

add_action('woocommerce_after_order_notes', 'my_custom_checkout_field');

function my_custom_checkout_field( $checkout ) {

    echo '<div id="my_custom_checkout_field"><h3>'.__('My Field').'</h3>';

    woocommerce_form_field( 'p_trade', array(
        'type'          => 'select',
        'class'         => array('p-trade orm-row-wide'),
        'label'         => __('Trade Details'),
        'placeholder'   => __('Enter a number'),
        'clear'     => true,
        'options' => array( 'trade-1' => 'Trade One', 'trade-2' => 'Trade Two', 'trade-3' => 'Trade Three', 'trade-4' => 'Trade Four' )
        ), $checkout->get_value( 'p_trade' ));

        woocommerce_form_field( 'p_retail', array(
            'type'          => 'select',
            'class'         => array('p-retail orm-row-wide'),
            'label'         => __('Retail Details'),
            'placeholder'   => __('Enter a number'),
            'clear'     => true,
            'options' => array('retail-1' => 'Retail One', 'retail-2' => 'Retail Two', 'retail-3' => 'Retail Three', 'retail-4' => 'Retail Four')
        ), $checkout->get_value( 'p_retail' ));
    echo '</div>';
}

/* Update the order meta with field value */

add_action('woocommerce_checkout_update_order_meta', 'my_custom_checkout_field_update_order_meta');
function my_custom_checkout_field_update_order_meta( $order_id ) {
    if ($_POST['p_trade']) update_post_meta( $order_id, 'p_trade', esc_attr($_POST['p_trade']));
    if ($_POST['p_retail']) update_post_meta( $order_id, 'p_retail', esc_attr($_POST['p_retail']));
}

/* Add the fields to order email */

add_filter( 'woocommerce_email_order_meta_keys', 'my_custom_checkout_field_order_meta_keys' );
function my_custom_checkout_field_order_meta_keys( $keys ) {
                echo '<h3>Payment Option:</h3>';
        $keys['Trade'] = 'p_trade';
        $keys['Retail'] = 'p_retail';
        return $keys;
}
?>