实例:

 

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
      	<title>Find latitude and longitude with Google Maps</title>
    <script src="http://maps.google.com/maps?file=api&v=2&key=ABQIAAAAgrj58PbXr2YriiRDqbnL1RSqrCjdkglBijPNIIYrqkVvD1R4QxRl47Yh2D_0C1l5KXQJGrbkSDvXFA"
      type="text/javascript"></script>
    <script type="text/javascript">

 function load() {
      if (GBrowserIsCompatible()) {
        var map = new GMap2(document.getElementById("map"));
        map.addControl(new GSmallMapControl());
        map.addControl(new GMapTypeControl());
        var center = new GLatLng(40.7862,-73.9753);
        map.setCenter(center, 15);
        geocoder = new GClientGeocoder();
        var marker = new GMarker(center, {draggable: true});  
        map.addOverlay(marker);
        document.getElementById("lat").innerHTML = center.lat().toFixed(5);
        document.getElementById("lng").innerHTML = center.lng().toFixed(5);

	  GEvent.addListener(marker, "dragend", function() {
       var point = marker.getPoint();
	      map.panTo(point);
       document.getElementById("lat").innerHTML = point.lat().toFixed(5);
       document.getElementById("lng").innerHTML = point.lng().toFixed(5);

        });


	 GEvent.addListener(map, "moveend", function() {
		  map.clearOverlays();
    var center = map.getCenter();
		  var marker = new GMarker(center, {draggable: true});
		  map.addOverlay(marker);
		  document.getElementById("lat").innerHTML = center.lat().toFixed(5);
	   document.getElementById("lng").innerHTML = center.lng().toFixed(5);


	 GEvent.addListener(marker, "dragend", function() {
      var point =marker.getPoint();
	     map.panTo(point);
      document.getElementById("lat").innerHTML = point.lat().toFixed(5);
	     document.getElementById("lng").innerHTML = point.lng().toFixed(5);

        });
 
        });

      }
    }

	   function showAddress(address) {
	   var map = new GMap2(document.getElementById("map"));
       map.addControl(new GSmallMapControl());
       map.addControl(new GMapTypeControl());
       if (geocoder) {
        geocoder.getLatLng(
          address,
          function(point) {
            if (!point) {
              alert(address + " not found");
            } else {
		  document.getElementById("lat").innerHTML = point.lat().toFixed(5);
	   document.getElementById("lng").innerHTML = point.lng().toFixed(5);
		 map.clearOverlays()
			map.setCenter(point, 14);
   var marker = new GMarker(point, {draggable: true});  
		 map.addOverlay(marker);

		GEvent.addListener(marker, "dragend", function() {
      var pt = marker.getPoint();
	     map.panTo(pt);
      document.getElementById("lat").innerHTML = pt.lat().toFixed(5);
	     document.getElementById("lng").innerHTML = pt.lng().toFixed(5);
        });


	 GEvent.addListener(map, "moveend", function() {
		  map.clearOverlays();
    var center = map.getCenter();
		  var marker = new GMarker(center, {draggable: true});
		  map.addOverlay(marker);
		  document.getElementById("lat").innerHTML = center.lat().toFixed(5);
	   document.getElementById("lng").innerHTML = center.lng().toFixed(5);

	 GEvent.addListener(marker, "dragend", function() {
     var pt = marker.getPoint();
	    map.panTo(pt);
    document.getElementById("lat").innerHTML = pt.lat().toFixed(5);
	   document.getElementById("lng").innerHTML = pt.lng().toFixed(5);
        });
 
        });

            }
          }
        );
      }
    }
    </script>
</head>

  
<body οnlοad="load()" οnunlοad="GUnload()" >
   <p><b> Find coordinates by moving around the map</b></p> <p>1. Drag and drop the map to broad location. <br/>
	2. Zoom in for greater accuracy. <br/>
	3. Drag and drop the marker to pinpoint the place. The coordinates are refreshed at the end of each move.  </p>
  <p><b>Find coordinates using the name and/or address of the place</b></p>

  <p>Submit the full location : number, street, city, country. For big cities and famous places, the country is optional. "Bastille Paris" or "Opera Sydney" will do. <br/>
 </p>

  <form action="#" οnsubmit="showAddress(this.address.value); return false">
     <p>        
      <input type="text" size="60" name="address" value="new york ny" />
      <input type="submit" value="Search!" />
      </p>
    </form>

 <p align="left">
 
 <table  bgcolor="#FFFFCC" width="300">
  <tr>
    <td><b>Latitude</b></td>
    <td><b>Longitude</b></td>
  </tr>
  <tr>

    <td id="lat"></td>
    <td id="lng"></td>
  </tr>
</table>
 </p>
  <p>
  <div align="center" id="map" style="width: 600px; height: 400px"><br/></div>
   </p>
  </div>

</body>

</html>