function getByClass(oParent,sClass){

     var aEle = oParent.getElementsByTagName('*');

     var result = [];

     var re = new RegExp('\\b' + sClass + '\\b','i');

     for(var i=0;i<aEle.length;i++){

         if(re.test(aEle[i].className)){

             result.push(aEle[i]);

         }

     }

     return result;

 }