function selecttag(showContent,selfObj){
	// 操作标签
	var tag = document.getElementById("tags").getElementsByTagName("li");
	var taglength = tag.length;
	for(i=0; i<taglength; i++){
		tag[i].className = "";
	}
	selfObj.parentNode.className = "selecttag";
	// 操作内容
	for(i=0; j=document.getElementById("tagContent"+i); i++){
		j.style.display = "none";
	}
	document.getElementById(showContent).style.display = "block";	
}


function tab_choose(t,c,n){
	for(i=0;i<=3;i++){
		x="tab"+i;
		y="content"+i;
		document.getElementById(x).className="tab_off";
		document.getElementById(y).style.display="none";
		}
	document.getElementById(t).className="tab_on";
	document.getElementById(c).style.display="block";
	}