function emptyVerplicht(field)
		{
			if(field.value == "Verplicht in te vullen"){field.value = "";}
		}
		function fnInit(){
			for (i=0; i<document.all.length; i++)
					document.all(i).unselectable = "on";
			editbox.unselectable = "off";
		}
		 function NewWindow(mypage, myname, w, h, scroll) {
			var winl = (screen.width - w) / 2;
			var wint = (screen.height - h) / 2;
			winprops = 'height='+h+',width='+w+',top='+wint+',left='+winl+',scrollbars='+scroll+',resizable'
			win = window.open(mypage, myname, winprops)
			if (parseInt(navigator.appVersion) >= 4) 
			{
				win.window.focus(); 
			}
         }
		
		function getId(id)
		{
			theid = document.getElementById(id);
			return theid;
		}
		
		function hide(id)
		{
			if(document.getElementById(id))
			{
				document.getElementById(id).style.visibility='hidden';
			}
		}
		 function show(id)
		{
			if(document.getElementById(id))
			{
				document.getElementById(id).style.visibility='visible';
			}
		}
		function showhide(id)
		{
			if(document.getElementById(id))	{
				if(document.getElementById(id).style.visibility == "hidden"){
					show(id);
				}else{
					hide(id);
				}
			}
		}
		function showhidecollapse(id)
		{
			if(document.getElementById(id))	{
				if(document.getElementById(id).style.visibility == "hidden"){
					show(id);
					document.getElementById(id).style.position="relative";
				}else{
					hide(id);
					document.getElementById(id).style.position="absolute";
				}
			}
		}

		function terug(){
			if(history.length > 0){
				document.write("<a href=''>< vorige pagina</a>");
			}
			else
			{
				document.write("");
			}
		}