function showroute() {
  var destaddr = document.getElementById('ziel').value;
  var startaddr = document.getElementById('strasse').value + ' ' + document.getElementById('nummer').value + ', ' + document.getElementById('plz').value + ' ' + document.getElementById('ort').value;

  document.getElementById('saddr').value = startaddr;
  document.getElementById('daddr').value = destaddr;
  
  if ((document.getElementById('strasse').value == '') || (document.getElementById('ort').value == '') || (document.getElementById('plz').value == '') || (document.getElementById('strasse').value == 'Bitte ausfüllen!') || (document.getElementById('ort').value == 'Bitte ausfüllen!') || (document.getElementById('plz').value == 'Bitte ausfüllen!')) {
    if (document.getElementById('strasse').value == '') { setmandatory('strasse');}
    if (document.getElementById('ort').value == '') { setmandatory('ort');}
    if (document.getElementById('plz').value == '') { setmandatory('plz');}
    return false;
  }
  else {
  
    //document.getElementById('search_route').action = "http://maps.google.de/?hl=de";
    document.getElementById('search_route').action = "index.php?id=92";
    document.getElementById('search_route').submit();
  }

  //alert(startaddr);
}

function setmandatory(id) {
  document.getElementById(id).style.color = '#ff0000';
  document.getElementById(id).value = 'Bitte ausfüllen!';
  
}

function unsetmandatory(id) {
  document.getElementById(id).style.color = '#000000';
  document.getElementById(id).value = '';
  
}