Get Elements By Class Name

1.function getElementsByClassName(classname, node) {
2. if(!node) node = document.getElementsByTagName("body")[0];
3. var a = [];
4. var re = new RegExp('\\b' + classname + '\\b');
5. var els = node.getElementsByTagName("*");
6. for(var i=0,j=els.length; i7. if(re.test(els[i].className))a.push(els[i]);
8. return a;
9.}