// JavaScript Document
function $(s) {
    return document.getElementById(s) ? document.getElementById(s) : s;

}
function findPosX(obj)
 {
    var curleft = 0;
    if (obj.offsetParent)
    {
        while (obj.offsetParent)
        {
            curleft += obj.offsetLeft
            obj = obj.offsetParent;

        }

    }
    else if (obj.x)
    curleft += obj.x;
    return curleft;

}
function findPosY(obj)
 {
    var curtop = 0;
    if (obj.offsetParent)
    {
        while (obj.offsetParent)
        {
            curtop += obj.offsetTop
            obj = obj.offsetParent;

        }

    }
    else if (obj.y)
    curtop += obj.y;
    return curtop;

}
var currPcnNav = null;
function pcnNav(o) {
    var offLeft = findPosX(o);
    var offTop = findPosY(o);
    var arrNav = document.getElementById("subNav").getElementsByTagName("ul");
    if (currPcnNav != null) {
        hidPcnNav(currPcnNav);

    }
    if (o.getAttribute("urn") != "null") {
        shwPcnNav($(o.getAttribute("urn")), offLeft);
        currPcnNav = $(o.getAttribute("urn"));
        document.body.onmouseup = function() {
            hidPcnNav(currPcnNav);

        }

    } else {
        currPcnNav ? hidPcnNav(currPcnNav) : "";

    }

}
function shwPcnNav(o, n) {
    o.style.display = "";
    o.style.left = n + "px";

}
function hidPcnNav(o) {
    o.style.display = "none";
    document.body.onmouseup = null;

}
function pcnNavInit() {
    var arrNav = document.getElementById("nav").getElementsByTagName("a");
    for (var i = 0; i < arrNav.length; i++) {
        arrNav[i].onmouseover = function() {
            pcnNav(this);

        }

    }

}

function ajax(url)
 {
    http_request = false;
    if (window.XMLHttpRequest)
    {

        http_request = new XMLHttpRequest()
        if (http_request.overrideMimeType)
        {
            http_request.overrideMimeType('text/xml');

        }

    }
    else if (window.ActiveXObject)
    {
        try
        {
            http_request = new ActiveXObject("Msxml2.XMLHTTP");

        }
        catch(e)
        {
            try
            {
                http_request = new ActiveXObject("Microsoft.XMLHTTP");

            }
            catch(e)
            {
                }

        }

    }
    if (!http_request) {
        alertLAC('您的浏览器不支持本站某些功能！');
        return false;
    }
    http_request.onreadystatechange = alertLACContents;
    http_request.open('GET', url, true);
    http_request.setRequestHeader("If-Modified-Since", "0");
    http_request.send(null);

}
function alertLACContents()
 {

    if (http_request.readyState == 4)
    {
        if (http_request.status == 200) {
            ajaxdo(http_request.responseText);
        }

    }
    else
    {
        //alert('网络连接不正常，请检查网络！');
        }

}