Copy billing information into contact information for 2Dialog forms. *Add IDs to each HTML field, make them match the ones in the script. *Add a checkbox that will work as the control that will trigger the copy. <input id="fill_contact" style="vertical-align: middle" mce_style="vertical-align: middle" type="checkbox"> Same as Billing Information…

copy_billing_info.js

(function($, $$){

    $('fill_contact').observe('click', function(e) {

		var name            = $('billing_name').getValue()
		,	billing_address = $('billing_address').getValue()
		,	billing_city    = $('billing_city').getValue()
		,	billing_state   = $('billing_state').getValue()
		,	billing_zip     = $('billing_zip').getValue()
		,	billing_phone   = $('billing_phone').getValue()
		,	billing_email   = $('billing_email').getValue();

		if( e.target.checked ){
			name = name == '' ? name : name.trim().split(/\s+/);
			var first_name = name[0] || '';
			var last_name  = name[1] || ''; 
			$('contact_first_name').setValue( first_name );
			$('contact_last_name').setValue( last_name );
			$('contact_email').setValue( billing_email );
			$('contact_address').setValue( billing_address );
			$('contact_city').setValue( billing_city );
			$('contact_state').setValue( billing_state );
			$('contact_zip').setValue( billing_zip );
			$('contact_phone').setValue( billing_phone );
		} else {
			$('contact_first_name').setValue( '' );
			$('contact_last_name').setValue( '' );
			$('contact_email').setValue( '' );
			$('contact_address').setValue( '' );
			$('contact_city').setValue( '' );
			$('contact_state').setValue( '' );
			$('contact_zip').setValue( '' );
			$('contact_phone').setValue( '' );
		}

	});

})($, $$);