var bw = checkBrowser();

function checkBrowser(){
  this.os=navigator.OS
  this.ver=navigator.appVersion
  this.dom=document.getElementById?1:0
  this.ie6=(this.ver.indexOf("MSIE 6")>-1 && this.dom)?1:0;
  this.ie5=(this.ver.indexOf("MSIE 5")>-1 && this.dom)?1:0;
  this.ie4=(document.all && !this.dom)?1:0;
  this.ns6=(!document.all && document.getElementById) ? true : false;
  this.ns5=(this.dom && parseInt(this.ver) == 5) ?1:0;
  this.ns4=(document.layers && !this.dom)?1:0;
  this.bw=(this.ie5 || this.ie4 || this.ns4 || this.ns5 || this.ns6)
  this.macOS = navigator.userAgent.indexOf('Mac')!=-1;
  this.winOS = navigator.userAgent.indexOf('Win')!=-1;
  return this;
}

function show(id){
  if (bw.ns4){
    document.layers[id].visibility = "show";
  }
  else if (bw.ns6){
    document.getElementById(id).style.visibility= "visible";
  }
  else if (bw.ie4 || bw.ie5 || bw.ie6){
    document.all[id].style.visibility = "visible";
  }
}

function hide(id){
  if (bw.ns4){
    document.layers[id].visibility = "hide";
  }
  else if (bw.ns6){
    document.getElementById(id).style.visibility= "hidden";
  }
  else if (bw.ie4 || bw.ie5 || bw.ie6){
    document.all[id].style.visibility = "hidden";
  }
}

function changeImage(id,imgName,imgObj){
	if (document.images){
		if (document.layers && layer!=null){
			//alert("layer!= null");
			eval('document.'+layer+'.document.images["'+imgName+'"].src = '+imgObj+'.src');
		}
		else{
			//alert("layer was null. setting document.images["+imgName+"].src to "+imgObj);
			document.images[imgName].src = eval(imgObj+".src");
		}
	}
}

function getLayer(id){
    if (bw.ns6 || bw.ie5&&bw.macOS){
      var layer = document.getElementById(id).style;
    }
    if (bw.ns4){
      var layer = document.id;
    }
    else if (bw.ie4 || bw.ie5 || bw.ie6){
      var layer = eval(id).style;
    }
    layer.x = parseInt(layer.left);
    layer.y = parseInt(layer.top);
    return layer;
}