Dynamic content in popup

HTML

<link rel="stylesheet" href="http://cdn.leafletjs.com/leaflet-0.7.3/leaflet.css">
<script src="http://cdn.leafletjs.com/leaflet-0.7.3/leaflet-src.js"></script>
<div id="map" ></div>

CSS

#map {
    height: 400px;
}

JavaScript

var lat = 46.566414;
var lng =  2.4609375;
var zoom =  5;

var map = new L.Map('map');

var osmUrl='http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png';
var osmAttrib='Map data &copy; OpenStreetMap contributors';
var osm = new L.TileLayer(osmUrl, {minZoom: 3, maxZoom: 8, attribution: osmAttrib});
map.addLayer(osm);

map.setView(new L.LatLng(lat, lng), zoom);

var marker = new L.Marker([48.862312, 2.332317]);
var marker1 = new L.Marker([48.864312, 2.332317]);
var popup = new L.Popup();

marker.addTo(map);
marker1.addTo(map)
var obj={};
obj.id="1";
marker.on('mouseover', function(evt) {
	console.log(this);
  evt.target.unbindPopup()
  evt.target.bindPopup(obj.id).openPopup();
});
marker.on('click', function(evt) {
   evt.target.unbindPopup();
    evt.target.bindPopup('a').openPopup();
});