G.Maps 地理位置方向值。怎么做?

G.Maps Geolocation Directions Value. How Do?

然后我从 google 地图中获取此代码作为方向并开始工作,但我想将其作为 "start " 我的位置。地理定位的代码已经在里面了。 代码是这样的:

像这样

<style>
#map-canvas {
  height: 400px;
}
</style>
<div id="map-canvas"></div>
<div id="panel">
  <b>Start: </b>
  <select id="start" onchange="updateRoute();">
    <option value="My position (??)">My Position</option>
  </select>
  <b>End: </b>
  <select id="end" onchange="updateRoute();">
    <option value="Padova PD, It">Padova</option>
    <option value="Milano">Parco</option>
  </select>
</div>
<script type="text/javascript" src="http://maps.googleapis.com/maps/api/js?sensor=true"></script>
<script>
  var directionsDisplay;
  var directionsService = new google.maps.DirectionsService();
  var map;
  var mylocation = new google.maps.LatLng(45.4064349,11.876761100000067);   // default location.  When geolocation tracks the client, this variable is set to that location

  function initialize() {
    var mapOptions = {
      zoom: 14,
      mapTypeId: google.maps.MapTypeId.HYBRID
    };
    directionsDisplay = new google.maps.DirectionsRenderer();
    map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
    directionsDisplay.setMap(map);
    map.setCenter(mylocation);
  }
  function updateRoute() {
    calcRoute(mylocation);
  }
  function calcRoute(start) {
    // var start = document.getElementById('start').value;
    var end = document.getElementById('end').value;
    var request = {
        origin:start,
        destination:end,
        travelMode: google.maps.TravelMode.DRIVING
    };
    directionsService.route(request, function(response, status) {
      if (status == google.maps.DirectionsStatus.OK) {
        directionsDisplay.setDirections(response);
      }
    });
  }

  // Try HTML5 geolocation
  if(navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(function(position) {
      mylocation = new google.maps.LatLng(position.coords.latitude, position.coords.longitude);
      //document.getElementById('start').value = ;
      if (map) {
        calcRoute(position.coords.latitude +','+ position.coords.longitude);
      }
    })
  }

  google.maps.event.addDomListener(window, 'load', initialize);
</script>