php – 搜索地址与google maps api v3上最近的现有地标之间的距离

我正在开发一个包含Google Maps API v3的网页.我目前有一个功能图和搜索栏.我需要能够在地图上的某个KML文件上显示搜索地址到最近地标的距离.我怎样才能做到这一点？

这是页面的代码：

<script type="text/javascript">
    var geocoder;
    var map; 
    var marker;
    var layers = [];
  function initialize() {
    geocoder = new google.maps.Geocoder ();
    var latlng = new google.maps.LatLng (41, -73.4);
    var myOptions = {
      zoom: 7,
      center: latlng,
      mapTypeId: google.maps.MapTypeId.ROADMAP
        }
      map = new google.maps.Map(document.getElementById("map_canvas"),
        myOptions);
      marker = new google.maps.Marker({map:map});


        layers[0] = new google.maps.KmlLayer('http://dl.dropBox.com/u/80233620/South-and-north-County-Trailway.kml',
            {preserveViewport: true});
        layers[1] = new google.maps.KmlLayer('http://www.nyc.gov/html/dot/downloads/misc/cityracks.kml', 
            {preserveViewport: true});
        layers[2] = new google.maps.KmlLayer('http://dl.dropBox.com/u/80233620/NWS%20Radar%20Images.kmz', 
            {preserveViewport: true});
    for (var i = 0; i < layers.length; i++) {
                layers[i].setMap(map);
              }
        }

    function codeAddress () {
        var address = document.getElementById ("address").value;
        geocoder.geocode ( { 'address': address}, function(results, status)  {
        if (status == google.maps.GeocoderStatus.OK)  {
            map.setCenter(results [0].geometry.location);
            marker.setPosition(results [0].geometry.location);
            map.setZoom(14);
            } 
        else {
            alert("Geocode was not successful for the following reason: " + status);
                }
        }); 
                            }
    function toggleLayer(i) {
      if(layers[i].getMap() === null) {
        layers[i].setMap(map);
      }
      else {
        layers[i].setMap(null);}
    }

</script>

解决方法:

您无法像这样访问KML图层中的数据

https://developers.google.com/maps/documentation/javascript/layers#KMLLayers

Because KML may include a large number of features, you may not access
feature data from the KmlLayer object directly. Instead, as features
are displayed, they are rendered to look like clickable Maps API
overlays.

相反,您可以处理XML并手动添加标记,然后使用geometry library和computedistanceBetween()来获取距离.我通常将距离乘以某个数来考虑转弯(距离公式得到直线距离).我相信大约1.2是最准确的.