One option might be to do something like this:
<script type="text/javascript">
dojo.require('esri.layers.FeatureLayer');
var baseURL;
var map;
function init() {
var initExtent = new esri.geometry.Extent({"xmin":-8590965,"ymin":4695877,"xmax":-8553434,"ymax":4711164,"spatialReference":{"wkid":102100}});
map = new esri.Map("map",{extent:initExtent});
var basemap = new esri.layers.ArcGISTiledMapServiceLayer("http://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer");
map.addLayer(basemap);
baseURL = "http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/HomelandSecurity/operations/FeatureServer";
esri.request({
url:baseURL,
content:{f:"json"},
callbackParamName:"callback",
load:addLayers,
error:esriConfig.defaults.io.errorHandler
});
}
function addLayers(response,args){
dojo.forEach(response.layers,function(layer){
var featureLayer = new esri.layers.FeatureLayer(baseURL + "/" + layer.id,{
mode: esri.layers.FeatureLayer.MODE_ONDEMAND,
outFields: ["*"]
});
map.addLayer(featureLayer);
});
}
dojo.addOnLoad(init);
</script>