window.onload=function(){
	waterfall('main','box');
	}
	function?waterfall(parent,box){
		var?oParent=document.getElementById(parent);
		var?oBoxs=getByClass(oParent,box);
		console.log(oBoxs.length);
		}
	function?getByClass(parent,clsName){
			var?boxArr=new?Array(),
			oElements?=parent.getElementsByTagName("*");
				?for(var?i=0;i<oElements.length;i++){
					?if(oElements[i].className==clsName){
						?boxArr.push(oElements[i]);
						
						?}
						?}
						?return?boxArr;
						?}		

console.log（oBoxs.length）只輸出1，不是應(yīng)該輸出相應(yīng)class的個(gè)數(shù)嗎？

還是說getByClassh函數(shù)沒有起作用？