duddlebug on "[Plugin: Contact Form 7] Send a client copy with radio buttons"

will this work will radio buttons.

add_filter( 'wpcf7_additional_mail', 'my_wpcf7_use_mail_2_or_not', 10, 2 );

function my_wpcf7_use_mail_2_or_not( $additional_mail, $cf ) {
	if ( 'yes' != $cf->posted_data['sendcopy'] )
		$additional_mail = array();

	return $additional_mail;
}

[radio Sendacopy id:Sendacopy "Yes" "No"]

https://wordpress.org/plugins/contact-form-7/