ECSTORE导航吸顶功能

ecstore导航吸顶功能，在导航父元素中加入id，如：

 <div id="mainNav1"></div> 

在footer.html中添加以下js代码:

    <script type="text/javascript">function getTop(e)
    {
        var offset=e.offsetTop;
        if(e.offsetParent!=null) //只要还有父元素,也就是当前元素不是根节点就继续往上累计元素的高度
            offset+=getTop(e.offsetParent);
        return offset;
    }
    var myBlockTop = getTop(document.getElementById("mainNav1"));
    var oneDiv=document.getElementById("mainNav1");
    if(!!window.attachEvent)//ie浏览器下。
    {
        window.attachEvent('**croll',function(){
                        if(document.documentElement.scrollTop/* +  (document.body.clientHeight || window.innerHTML) */>= myBlockTop)
                        {oneDiv.style.position="fixed";oneDiv.style.top="0";oneDiv.style.left="0";oneDiv.style.display="block";oneDiv.style.zIndex="9999999999999";oneDiv.style.height="35px";oneDiv.innerHTML = document.getElementById("mainNav").innerHTML; }
                        else{oneDiv.style.display="none";}
 
        });
    }
    if(!!window.addEventListener)//非ie浏览器下
    {
        window.addEventListener("scroll",function(){//document.body.scrollTop可保证chrome的正常。
            if(document.documentElement.scrollTop/* +  (document.body.clientHeight || window.innerHTML) */>= myBlockTop||document.body.scrollTop>=myBlockTop)
            {oneDiv.style.position="fixed";oneDiv.style.top="0";oneDiv.style.width="100%";oneDiv.style.zIndex="9999999999999";oneDiv.style.display="block";oneDiv.style.height="35px";oneDiv.innerHTML =document.getElementById("mainNav").innerHTML;}
            else{oneDiv.style.display="none";}
        });
    }</script>

测试看看效果吧~