var ie4 = (document.all);
var ns4 = (document.layers);
var ns6 = (document.getElementById && !document.all);
//--
function show( layer ){
  isVisible( layer ) ? hidelayer( layer ) : showlayer( layer );
}//end function show
//--
function hidelayer(layer) {
  if( ie4 || ns6 ){
    document.getElementById(layer).style.display = "none";
  }else if( ns4 ){
    document.layers[layer].visibility = "hide";
  }  
}//end function hidelayer
//--
function showlayer(layer) {      
  if( ie4 || ns6 ){
    document.getElementById(layer).style.display = "block";
    return document.getElementById(layer);
  }else if( ns4 ){
    document.layers[layer].visibility = "show";
  }  
}//end function showLayer
//--
function isVisible( layer ){
  if( ie4 || ns6 ){
    return ( document.getElementById(layer).style.display == "block" );
  }else if( ns4 ){
    return ( document.layers[layer].visibility == "show" );
  }
}//end function is visible
//--
function writeLayer(layerID,txt){
  if( ns6 ){
    document.getElementById(layerID).innerHTML=txt;
  }else if( ie4 ){
    document.getElementById(layerID).innerHTML=txt;
    //document.all[layerID].innerHTML=txt;
  }else if( ns4 ){
    with(document.layers[layerID].document){
      open();
      write(txt);
      close();
    }
  }
}//end function writeLayer
function addLayerContent( layerID,txt){
  if( ns6 ){
    var tmp = document.getElementById(layerID).innerHTML;
    document.getElementById(layerID).innerHTML = tmp + txt;
  }else if( ie4 ){
    var tmp = document.all[layerID].innerHTML;
    document.all[layerID].innerHTML = tmp + txt;
  }
}//end function addLayerContent
function getLayerContent(layerID){
  if( ns6 ){
    return document.getElementById(layerID).innerHTML;
  }else if( ie4 ){
    return document.all[layerID].innerHTML;
  }
}//end function getLayerContent
//--