//友情链接select选择后，打开对应链接
function location_yq(s) {
    var d = s.options[s.selectedIndex].value;    
      window.open(d);
}

//iframe自适应高度
function dyniframesize(down) {
    var pTar = null;
    if (document.getElementById) {
        pTar = document.getElementById(down);
    }
    else {
        eval('pTar = ' + down + ';');
    }
    if (pTar && !window.opera) {
        //begin resizing iframe 
        pTar.style.display = "block"
        if (pTar.contentDocument && pTar.contentDocument.body.offsetHeight) {
            //ns6 syntax 
            pTar.height = pTar.contentDocument.body.offsetHeight;


        }
        else if (pTar.Document && pTar.Document.body.scrollHeight) {
            //ie5+ syntax 
            pTar.height = pTar.Document.body.scrollHeight;

        }

    }
}

//导航栏效果实现
var timeout = 5000;
var closetimer = 0;
var ddmenuitem = 0;
// open hidden layer
function mopen(id) {

    // cancel close timer
    mcancelclosetime();

    // close old layer
    if (ddmenuitem) ddmenuitem.style.visibility = 'hidden';

    // get new layer and show it
    ddmenuitem = document.getElementById(id);
    ddmenuitem.style.visibility = 'visible';
}
// close showed layer
function mclose() {
    if (ddmenuitem) ddmenuitem.style.visibility = 'hidden';
}
// go close timer
function mclosetime() {
    closetimer = window.setTimeout(mclose, timeout);
}
// cancel close timer
function mcancelclosetime() {
    if (closetimer) {
        window.clearTimeout(closetimer);
        closetimer = null;
    }
}
// close layer when click-out
document.onclick = mclose;


//导航栏图片更换
function UpImage(s) {
     document.getElementById("div_menuimage").innerHTML = s;
}