function putIF(hldr,url) 
{
   holder=document.getElementById(hldr); //wrap around div
   holder.style.display='block';  // the div gets styled
   holder.style.left=610;
   holder.style.top=10;
   holder.style.width=400;
   IF=document.createElement('iframe');  // iframe is created in the DOM
   IF.setAttribute('height', 400);  // simple DOM methods
   IF.setAttribute('width', 400);
   IF.setAttribute("src", url);
   holder.appendChild(IF); // now we add it to the div
   holder.innerHTML+='<button style=width:400px onclick="closeIF(this.parentNode)">Sluit dit venster</button>';
     // final step is to put in additional controls
}
   function closeIF(obj)
   {
      obj.innerHTML='';
      obj.style.display='none';
   }