var DHTML = (document.getElementById || document.all || document.layers);

function getObj(name)
{
    if(document.getElementById)
    {
        this.obj = document.getElementById(name);
        this.style = document.getElementById(name).style;
    }
    else if(document.all)
    {
        this.obj = document.all[name];
        this.style = document.all[name].style;
    }
    else if(document.layers)
    {
        this.obj = document.layers[name];
        this.style = document.layers[name];
    }
}

function visibility(name, flag)
{
    if (!DHTML) return;

    var x = new getObj(name);
    x.style.visibility = (flag) ? 'hidden' : 'visible';
}