openlayers地图全屏显示的代码

最近项目需要，着手GeoServer+Udig+Openlayers搭建本地地图服务器，第一次接触这些东西，参考了网上很多相关文章，如今初有感觉，但仍属入门。近日项目需要，故在Openlayers官网上认真学习了很Demo,初见成效。Demo真是个好东西，比较直观，以下对全屏控制代码：

 

var map = new OpenLayers.Map({
    div: "map",
    layers: [
        new OpenLayers.Layer.OSM("OSM (without buffer)"),
        new OpenLayers.Layer.OSM("OSM (with buffer)", null, {buffer: 2})
    ],
    controls: [
        new OpenLayers.Control.Navigation({
            dragPanOptions: {
                enableKinetic: true
            }
        }),
        new OpenLayers.Control.PanZoom(),
        new OpenLayers.Control.Attribution()
    ],
    center: [0, 0],
    zoom: 3
});

map.addControl(new OpenLayers.Control.LayerSwitcher());