Snippet : Add dynamic data to Contact form 7 email

wordpress-cf7-mail-tag.php

<?php
add_filter('wpcf7_special_mail_tags', 'add_prospectus_link_to_email', 10, 3);
function add_prospectus_link_to_email($output, $name, $html)
{
    $name = preg_replace('/^wpcf7\./', '_', $name); // for back-compat

    if ('prospectus' == $name) {
        $prospectus = get_field('prospectus', 'options');
  		return $prospectus['url'];
    }

    return $output;
}