function disable_element( inputid, checkbx )
{
       var textfld = document.getElementById(inputid);

       if (checkbx.checked)
                textfld.disabled = false;
       if (!checkbx.checked)
                textfld.disabled = true;
}

function add_focus( inputid )
{
     var textfld = document.getElementById(inputid);

     if ( !textfld.disabled )
     {
           document.getElementById( inputid ).focus();
     }
}

function empty_field( field, standaard )
{
      var inhoud = document.getElementById( field );


      if ( inhoud.value == standaard )
      {
             inhoud.value = "";
      }

}

function update_prijs( we )
{
     getal=5.775993992
getal=Math.round(getal*10)/10;

alert(getal);
}

function bevestig( bericht)
{



    if (bericht == '' || typeof(window.opera) != 'undefined')
    {
        return true;
    }

    return confirm(bericht);
}

function b_alert( plaatje, titel, prijs )
{
  alertwidth = 400;


  screenwidth = window.screen.availWidth;
  screenheight = window.screen.availHeight;

  screenwidth = (screenwidth/2);
  screenheight = (screenheight/2)-50;

  x_start = (screenwidth-(alertwidth/2));
  y_start = (screenheight-200);

  document.getElementById('b_alert').style.width = alertwidth;
  document.getElementById('b_alert').style.top = y_start;
  document.getElementById('b_alert').style.left = x_start;

  document.getElementById('b_alert_text').innerHTML = '<table width="100%"><td width="30%"><img src="' + plaatje + '" alt="" border=0></td><td width="70%" bgcolor="#f6f6f6" valign="top"><b> ' + titel + ' </b><p> <span class="prijs">&euro; ' + prijs + '</span></td><tr><td colspan="2" bgcolor="#EAEAEA"></td></table>';
}

function hide_b_alert()
{
document.getElementById('b_alert').style.width = 0;
document.getElementById('b_alert').style.top = -5000;
document.getElementById('b_alert').style.left = -5000;
document.getElementById('b_alert_text').innerHTML = "";
}


function verander_class( id, naar )
{
   document.getElementById( id ).className = naar;
}


function check_clicked( id )
{
   document.getElementById( id ).checked = true;
}

function openPopup(url,AAttr)
{
	  AWindow=window.open(url,window.name+"X",AAttr);

	  if(parseInt(navigator.appVersion)>=3)
		   AWindow.focus();

	  return ;
}

function afbeelding(url, width, height, urlalt, pid, basis)
{
	
	document.getElementById("afbeelding").innerHTML='<img src="' + url + '" width="' +  width + '" height="' + height + '">';
	document.getElementById("fotoVergroot").href=url;
	document.getElementById("fotoVergroot1").href=url;
	
}