How to disable submit button and change text on form submit at Wordpress "contact form 7" - Stack Overflow

// disable button after clicking on submit button
<?php add_action('wp_footer', 'mycustom_wp_footer');
function mycustom_wp_footer()
{
?>
    <script type="text/javascript">
        jQuery('.wpcf7-form').submit(function() {
            jQuery(this).find(':input[type=submit]').prop('disabled', true);
            var wpcf7Elm = document.querySelector('.wpcf7');
            wpcf7Elm.addEventListener('wpcf7submit', function(event) {
                jQuery('.wpcf7-submit').prop("disabled", false);
            }, false);
            wpcf7Elm.addEventListener('wpcf7invalid', function() {
                jQuery('.wpcf7-submit').prop("disabled", false);
            }, false);
        });
    </script>
<?php
}?>