javascript document.getElementsByClassName compatibility with IE

Question

What is the best method to retrieve an array of elements that have a certain class?

I would use document.getElementsByClassName but IE does not support it.

Answer 1

function _getClass(whatEverClasNameYouWant){
var a=document.getElementsByTagName('*');
   for(b in a){
      if((' '+a[b].className+' ').indexOf(' '+whatEverClasNameYouWant+' ')>-1){
      return a[b];
      }
   }
}