var Item = 1;//设置默认显示第几个Tab
function addClass(element,value) {
  if (!element.className) {
    element.className = value;
  } else {
    element.className+= " ";
    element.className+= value;
  }
}
function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}
function menuFix() {
var sfEls = document.getElementById("nav").getElementsByTagName("li");
for (var i=0; i<sfEls.length; i++) {
sfEls[i].onmouseover=function() {
this.className+=(this.className.length>0? " ": "") + "show";

}
sfEls[i].onmouseout=function() {
this.className=this.className.replace(new RegExp("( ?|^)show\\b"), "");
}
}
}
function tabs(){
	var tabs = document.getElementById("tabs");
	var h3s = tabs.getElementsByTagName("h3");
	/*将默认显示的tab高亮*/
	addClass(h3s[Item-1],"on");
	var divs = tabs.getElementsByTagName("div")[0];
	for(var i=0;i<divs.length;i++)
	{
		//将所有ul切换到JS支持状态下
		divs[i].className = "json";
		//将默认显示的Tab对应的内容显示
		if(i==Item-1) divs[Item-1].style.display = "";
		//将其他的Tab对应的内容隐藏
		else divs[i].style.display = "none";
	}
	for(var i=0;i<h3s.length;i++)
	{
		//将所有h3切换到JS支持状态下
		addClass(h3s[i]," json");
		//点击选项卡时进行切换
		h3s[i].onclick= function(){setTab(this);}
	}
}
function setTab(whichtab) {
	//获取当前鼠标点击标题时外层DIV对应的ID
	var boxid = whichtab.parentNode.getAttribute("id");
	//截取ID最后一个数值
	var id=boxid.substr(boxid.length-1,1);
	currentItem = Item;
	//如果鼠标不是划过默认显示的Tab，才进行下一步的隐藏和切
    if (id!= currentItem) {
	var defaultBox=document.getElementById("box"+currentItem);
	//隐藏当前显示的Tab对应的内容
	defaultBox.getElementsByTagName("div")[0].style.display = "none";
	//将当前显示的Tab切换到非高亮状态
	defaultBox.getElementsByTagName("h3")[0].className = "json";
    }
	var currentBox = document.getElementById("box"+id);
	//显示目标Tab对应的内容
	currentBox.getElementsByTagName("div")[0].style.display = "";
	//将目标Tab切换到高亮状
	addClass(currentBox.getElementsByTagName("h3")[0]," on");
	//Tab切换完成
	Item = id;//将当前Tab的数值存储到变量以供下一次调用
}

addLoadEvent(tabs);
addLoadEvent(menuFix);

$(document).ready(function(){
    $('#nav ul li:last-child').addClass("last");
  });