1 function $(id) {
2 return !id ? null : document.getElementById(id);
3 }
4 function display(id) {
5 var obj = $(id);
6 if(obj.style.visibility) {
7 obj.style.visibility = obj.style.visibility == 'visible' ? 'hidden' : 'visible';
8 } else {
9 obj.style.display = obj.style.display == '' ? 'none' : '';
10 }
11 }