function showhide($button, $form, $show, $hide)
{
	if(document.getElementById($form).style.display == 'block'){
		document.getElementById($form).style.display = 'none';
		document.getElementById($button).className = $hide;
	} else {
		document.getElementById($form).style.display = 'block';
		document.getElementById($button).className = $show;
	}
}