Adding ID's to google map markers

I have a script that loops and adds markers one at a time.

I am trying to get the current marker to have an info window and and only have 5 markers on a map at a time (4 without info windows and 1 with)

How would I add an id to each marker so that I can delete and close info windows as needed.

This is the function I am using to set the marker:

function codeAddress(address, contentString) {

var infowindow = new google.maps.InfoWindow({
  content: contentString
});

if (geocoder) {

  geocoder.geocode( { 'address': address}, function(results, status) {

    if (status == google.maps.GeocoderStatus.OK) {
       
        map.setCenter(results[0].geometry.location);

       var marker = new google.maps.Marker({
          map: map, 
          position: results[0].geometry.location
       });

       infowindow.open(map,marker);

      } else {
       alert("Geocode was not successful for the following reason: " + status);
      }
    });
  }

}

JavaScript is a dynamic language. You could just add it to the object itself.

var marker = new google.maps.Marker(markerOptions);
marker.metadata = {type: "point", id: 1};

Also, because all v3 objects extend MVCObject(). You can use:

marker.setValues({type: "point", id: 1});
// or
marker.set("type", "point");
marker.set("id", 1);
var val = marker.get("id");

Just adding another solution that works for me.. You can simply append it in the marker options:

var marker = new google.maps.Marker({
	map: map, 
	position: position,
	
	// Custom Attributes / Data / Key-Values
	store_id: id,
	store_address: address,
	store_type: type
});

And then retrieve them with:

marker.get('store_id');
marker.get('store_address');
marker.get('store_type');

I have a simple Location class that I use to handle all of my marker-related things. I'll paste my code below for you to take a gander at.

The last line(s) is what actually creates the marker objects. It loops through some JSON of my locations, which look something like this:

{"locationID":"98","name":"Bergqvist Järn","note":null,"type":"retail","address":"Smidesvägen 3","zipcode":"69633","city":"Askersund","country":"Sverige","phone":"0583-120 35","fax":null,"email":null,"url":"www.bergqvist-jb.com","lat":"58.891079","lng":"14.917371","contact":null,"rating":"0","distance":"45.666885421019"}

Here is the code:

If you look at the target() method in my Location class, you'll see that I keep references to the infowindow's and can simply open() and close() them because of a reference.

See a live demo: http://ww1.arbesko.com/en/locator/ (type in a Swedish city, like stockholm, and hit enter)

var Location = function() {
    var self = this,
        args = arguments;

    self.init.apply(self, args);
};

Location.prototype = {
    init: function(location, map) {
        var self = this;
    
        for (f in location) { self[f] = location[f]; }
    
        self.map = map;
        self.id = self.locationID;
    
        var ratings = ['bronze', 'silver', 'gold'],
            random = Math.floor(3*Math.random());
    
        self.rating_class = 'blue';
    
        // this is the marker point
        self.point = new google.maps.LatLng(parseFloat(self.lat), parseFloat(self.lng));
        locator.bounds.extend(self.point);
    
        // Create the marker for placement on the map
        self.marker = new google.maps.Marker({
            position: self.point,
            title: self.name,
            icon: new google.maps.MarkerImage('/wp-content/themes/arbesko/img/locator/'+self.rating_class+'SmallMarker.png'),
            shadow: new google.maps.MarkerImage(
                                        '/wp-content/themes/arbesko/img/locator/smallMarkerShadow.png',
                                        new google.maps.Size(52, 18),
                                        new google.maps.Point(0, 0),
                                        new google.maps.Point(19, 14)
                                    )
        });
    
        google.maps.event.addListener(self.marker, 'click', function() {
            self.target('map');
        });
    
        google.maps.event.addListener(self.marker, 'mouseover', function() {
            self.sidebarItem().mouseover();
        });
    
        google.maps.event.addListener(self.marker, 'mouseout', function() {
            self.sidebarItem().mouseout();
        });
    
        var infocontent = Array(
            '<div class="locationInfo">',
                '<span class="locName br">'+self.name+'</span>',
                '<span class="locAddress br">',
                    self.address+'<br/>'+self.zipcode+' '+self.city+' '+self.country,
                '</span>',
                '<span class="locContact br">'
        );
    
        if (self.phone) {
            infocontent.push('<span class="item br locPhone">'+self.phone+'</span>');
        }
    
        if (self.url) {
            infocontent.push('<span class="item br locURL"><a href="http://'+self.url+'">'+self.url+'</a></span>');
        }
    
        if (self.email) {
            infocontent.push('<span class="item br locEmail"><a href="mailto:'+self.email+'">Email</a></span>');
        }
    
        // Add in the lat/long
        infocontent.push('</span>');
    
        infocontent.push('<span class="item br locPosition"><strong>Lat:</strong> '+self.lat+'<br/><strong>Lng:</strong> '+self.lng+'</span>');
    
        // Create the infowindow for placement on the map, when a marker is clicked
        self.infowindow = new google.maps.InfoWindow({
            content: infocontent.join(""),
            position: self.point,
            pixelOffset: new google.maps.Size(0, -15) // Offset the infowindow by 15px to the top
        });
    
    },

    // Append the marker to the map
    addToMap: function() {
        var self = this;
    
        self.marker.setMap(self.map);
    },

    // Creates a sidebar module for the item, connected to the marker, etc..
    sidebarItem: function() {
        var self = this;
    
        if (self.sidebar) {
            return self.sidebar;
        }
    
        var li = $('<li/>').attr({ 'class': 'location', 'id': 'location-'+self.id }),
            name = $('<span/>').attr('class', 'locationName').html(self.name).appendTo(li),
            address = $('<span/>').attr('class', 'locationAddress').html(self.address+' <br/> '+self.zipcode+' '+self.city+' '+self.country).appendTo(li);
    
        li.addClass(self.rating_class);
    
        li.bind('click', function(event) {
            self.target();
        });
    
        self.sidebar = li;
    
        return li;
    },

    // This will "target" the store. Center the map and zoom on it, as well as 
    target: function(type) {
        var self = this;
    
        if (locator.targeted) {
            locator.targeted.infowindow.close();
        }
    
        locator.targeted = this;
    
        if (type != 'map') {
            self.map.panTo(self.point);
            self.map.setZoom(14);
        };
    
        // Open the infowinfow
        self.infowindow.open(self.map);
    }
};

for (var i=0; i < locations.length; i++) {
    var location = new Location(locations[i], self.map);
    self.locations.push(location);

    // Add the sidebar item
    self.location_ul.append(location.sidebarItem());

    // Add the map!
    location.addToMap();
};

Why not use an cache that stores each marker object and references an ID?

var markerCache= {};
var idGen= 0;

function codeAddress(addr, contentStr){
    // create marker
    // store
    markerCache[idGen++]= marker;
}

Edit: of course this relies on a numeric index system that doesn't offer a length property like an array. You could of course prototype the Object object and create a length, etc for just such a thing. OTOH, generating a unique ID value (MD5, etc) of each address might be the way to go.

Marker already has unique id

marker.__gm_id