/**
 * delete tag's attrbute
 * eg: removeTagAttribute('img', 'alt');
 * @param tagName
 * @param attrName
 * @return
 */
function removeTagAttribute(tagName, attrName) {
	
	var tags = document.getElementsByTagName(tagName)
	for (var i = 0; i < tags.length; i++) {
	    if (tags[i].getAttribute(attrName)) {
	    	tags[i].setAttribute(attrName, '');
	    }
	}
}
/**
 * open window with the addr
 * eg: openWindowByAddr('http://www.yy.com');
 * @param addr
 * @return
 */
function openWindowByAddr(addr) {
	if (addr && addr != '#'){
		window.open(addr);
	}
}

/**
 * change head column's CSS
 * eg: changeStyleClass('', '', '');
 * @param addr
 * @return
 */
function changeStyleClass(id, class_name1, class_name2) {
	var obj_select = document.getElementById(id);
	//alert(obj_select.parentNode.parentNode.tagName);
	var li = obj_select.parentNode.parentNode.childNodes;
	for(var i = 0; i < li.length; i++) {
		li[i].childNodes[0].className = class_name2;
	}
	obj_select.className = class_name1;
}