Marker from User Input

Application which shows a marker at user provided input

HTML

<script src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
<script src="http://dev.openlayers.org/releases/OpenLayers-2.13.1/OpenLayers.js"></script>
<div id="map"></div>
<div id="inputForm">Latitude:
  <input id="latitude" type="text" value="40"/>
  Longitude:
  <input id="longitude" type="text" value="-118"/>
  <input id="foo" type="button" value="Add Marker" />
</div>

CSS

#map {
    width:800x;
    height:400px;
}

JavaScript

var map, basemap, markers;
    $(document).ready(function () {
        init_map();
        $("#btn_addmarker").on("click", function () {
            var lat = $("#latitude").val();
            var lon = $("#longitude").val();
            add_marker(lat, lon);
        });
    });

    function init_map() {
        map = new OpenLayers.Map('map');
        basemap = new OpenLayers.Layer.OSM("Simple OSM Map");
        map.addLayer(basemap);
        markers = new OpenLayers.Layer.Markers("Markers");
        map.addLayer(markers);
        map.setCenter(
            new OpenLayers.LonLat(-71.147, 42.472).transform(
                new OpenLayers.Projection("EPSG:4326"),
                map.getProjectionObject()
            ), 12
        );
    }

    function add_marker(latitude, longitude) {
        var lonLat = new OpenLayers.LonLat(longitude, latitude)
            .transform(
                new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984
                map.getProjectionObject() // to Spherical Mercator Projection
        );
        var point = new OpenLayers.Marker(lonLat);
        markers.addMarker(point);
        map.setCenter(lonLat, 8);
        //console.log(latitude + ", " + longitude);
    }
    
    function foo(){
            var lonLat = new OpenLayers.LonLat(-117, 41)
            .transform(
                new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984
                map.getProjectionObject() // to Spherical Mercator Projection
        );
    	map.setCenter(lonLat, 1);
    }