PMPro - Add Notes to Order Columns in Admin and CSV

pmpro-add-notes-order-columns-admin-csv.php

<?php
/**
 * Adds a notes tab in the admin area and in the order CSV export.
 * 
 * You can add this recipe to your site by creating a custom plugin
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * Read this companion article for step-by-step directions on either method.
 * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */
/**
 * Add donation to Orders page and CSV export
 */
function my_pmprodon_init() {
    add_action('pmpro_orders_extra_cols_header', 'my_pmpro_orders_extra_cols_header');
    add_action('pmpro_orders_extra_cols_body', 'my_pmpro_orders_extra_cols_body');
    add_action('pmpro_orders_csv_extra_columns', 'my_pmpro_orders_csv_extra_columns');
}
add_action('init', 'my_pmprodon_init');

function my_pmpro_orders_extra_cols_header() {
    echo '<th>' . __('Notes', 'paid-memberships-pro') . '</th>';
}

function my_pmpro_orders_extra_cols_body($order) {
    echo '<td>' . wp_kses_post( $order->notes ) . '</td>';
}

function my_pmpro_orders_csv_extra_columns($columns) {
    $columns['notes'] = 'my_pmpro_orders_csv_notes';
	return $columns;
}
add_filter('pmpro_orders_csv_extra_columns', 'my_pmpro_orders_csv_extra_columns');

function my_pmpro_orders_csv_notes($order) {
    return $order->notes;
}