google地图多Marker 多infowindow

var map; //全局变量
function initialize() {
  var myLatlng = new google.maps.LatLng(-25.363882,131.044922);
  var myOptions = {
    zoom: 4,
    center: myLatlng,
    mapTypeId: google.maps.MapTypeId.ROADMAP
  }

  map = new google.maps.Map(document.getElementByIdx_x_x("map_canvas"), myOptions);

  // Add 5 markers to the map at random locations
  var southWest = new google.maps.LatLng(-31.203405,125.244141);
  var northEast = new google.maps.LatLng(-25.363882,131.044922);
  var bounds = new google.maps.LatLngBounds(southWest,northEast);
  map.fitBounds(bounds);
  var lngSpan = northEast.lng() - southWest.lng();
  var latSpan = northEast.lat() - southWest.lat();
  for (var i = 0; i < 5; i++) {
    var location = new google.maps.LatLng(southWest.lat() + latSpan * Math.random(),
        southWest.lng() + lngSpan * Math.random());
    var marker = new google.maps.Marker({
        position: location, 
        map: map
    });
    var j = i + 1;
    marker.setTitle(j.toString());
    attachSecretMessage(marker, i);//所以这里传值就不用传map值了
  }
}

// The five markers show a secret message when clicked
// but that message is not within the marker's instance data

function attachSecretMessage(marker, number) {
  var message = ["This","is","the","secret","message"];
  var infowindow = new google.maps.InfoWindow(
      { content: message[number],
        size: new google.maps.Size(50,50)
      });
  google.maps.event.addListener(marker, 'click', function() {
    infowindow.open(map,marker);
  });
}
http://code.google.com/intl/zh-CN/apis/maps/documentation/javascript/examples/event-closure.html