DOM操作通过类名获取元素

<span style="font-family:Microsoft YaHei;font-size:18px;">clsname是要获取元素的类名，parentId是要获取父元素id</span>

<span style="font-family:Microsoft YaHei;font-size:18px;">
</span>

<span style="font-family:Microsoft YaHei;font-size:18px;">function getElementsByClassName(clsname,parentId){
	var p = parentId?document.getElementById(parentId):document,
	      elements = [],
	      sonEle = document.getElementsByTagName("*");

		for(var i = 0;i<soneEle.length;i++){
			if(sonEle[i].className==clsname){
				elements.push(sonEle[i]);
			}
		}
		return elements;
}</span>