Get elements by class name in javascript

At times, i need function to get all the elements using class name in javascript. But since such function does not exist as in javascript, so i thought of creating a similar function that can be used to get elements by class name.
Here is the code snippet:

function getElementByClassName(strClassName) {
 var eleNames = new Array();
 var totalFrms = document.forms.length;
 for(var i = 0; i < totalFrms; i++) {
  //alert(document.forms[i].elements.length);
  var eleLen = document.forms[i].elements.length;
  for(var j = 0; j < eleLen; j++) {
   if(strClassName === document.forms[i].elements[j].className) {
   eleNames.push(document.forms[i].elements[j]);
   }
  }
 }
 return eleNames;
 /*
 for(t = 0; t  < eleNames.length; t++) {
  alert(eleNames[t].type);
 }
 */
}
getElementByClassName("user_text");
Thats is. Hope this helps someone.