About the scrolling navigation bar code at the top of the blog_javascript skills

Many friends have asked me through various methods for the code for the scrolling navigation menu at the top of the blog. In fact, it's nothing special, but since there is demand, I will sort out this part of the code for your reference.

Copy code The code is as follows:

 Anything here 
 Anything here 
 Anything here 

for(var t=0;t<1000;t ) document.writeln('Test content: line ' t '');


var g_myBodyInstance = document.body;
var g_myBodyInstanceString = "document.body";
if(document.compatMode != "BackCompat"){
    // for looser.dtd
    g_myBodyInstance = document.documentElement;
    g_myBodyInstanceString = "document.documentElement";
}
var isMinNS4 = (navigator.appName.indexOf("Netscape") >= 0 &&
                parseFloat(navigator.appVersion) >= 4) ? 1 : 0;
var isMinNS5 = (navigator.appName.indexOf("Netscape") >= 0 &&
                parseFloat(navigator.appVersion) >= 5) ? 1 : 0;
var isMinIE4 = (document.all) ? 1 : 0;
var isMinIE5 = (isMinIE4 && navigator.appVersion.indexOf("5.") >= 0) ? 1 : 0;
var isMacIE = (isMinIE4 && navigator.userAgent.indexOf("Mac") >= 0) ? 1 : 0;

var getFFVersion=navigator.userAgent.substring(
                    navigator.userAgent.indexOf("Firefox")).split("/")[1];
//extra height in px to add to iframe in FireFox 1.0  browsers
var FFextraHeight=getFFVersion<1.5? 16 : 0;


function getLayer(name) {
  if (isMinNS5)
    return document.getElementById(name);
  else if (isMinIE4)
    return eval('document.all.'   name);
  else if (isMinNS4)
    return findLayer(name, document);

  return null;
}

function findLayer(name, doc) {

  var i, layer;

  for (i = 0; i < doc.layers.length; i ) {
    layer = doc.layers[i];
    if (layer.name == name)
      return layer;
    if (layer.document.layers.length > 0) {
      layer = findLayer(name, layer.document);
      if (layer != null)
        return layer;
    }
  }

  return null;
}

function moveLayerTo(layer, x, y) {
  if (isMinIE4) {
    layer.style.left = x;
    layer.style.top  = y;
  }
  else if (isMinNS5) {
    layer.style.left = x 'px';
    layer.style.top  = y 'px';
  }
  else if (isMinNS4)
    layer.moveTo(x, y);
}

function getPageLeft(layer) {

  if (isMinIE4||isMinNS5)
    return(layer.offsetLeft);
  else if (isMinNS4)
    return(layer.pageX);
  return(-1);
}

function getPageTop(layer) {

  if (isMinIE4||isMinNS5)
    return(layer.offsetTop);
  else if (isMinNS4)
    return(layer.pageY);
  return(-1);
}

function getPageScrollX() {

  if (isMinIE4||isMinNS5)
    return(g_myBodyInstance.scrollLeft);
  else if (isMinNS4)
    return(window.pageXOffset);
  return(-1);
}

function getPageScrollY() {

  if (isMinIE4||isMinNS5)
    return(g_myBodyInstance.scrollTop);
  else if (isMinNS4)
    return(window.pageYOffset);
  return(-1);
}

var g_p_zealNavigatorBar = null;
g_p_zealNavigatorBar = getLayer('zealNavigatorBar');
if(!isMinIE4){g_p_zealNavigatorBar.style.position = 'fixed';}
function reposzealNavigatorBar(){
    if(isMinIE4){
        try{
            moveLayerTo(g_p_zealNavigatorBar, 
                        getPageLeft(g_p_zealNavigatorBar), 
                        getPageScrollY());
        }catch(e){}
    }
}
window.onresize = reposzealNavigatorBar;
window.onscroll = reposzealNavigatorBar;
window.onload = reposzealNavigatorBar;