ArcGIS API for JavaScript (legacy) ^3.46

new esri.layers.ArcGISDynamicMapServiceLayer(
  "https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer",
  {"opacity": 0.75});

console.log(layer.capabilities);

• Setting the layer ID in the layer constructor.

  population = new esri.layers.ArcGISDynamicMapServiceLayer("http://myserver/arcgis/rest/population/MapServer/Layers", {id:"population"});
  

• Setting the layer ID after a layer is initialized.

  population.id = "population";

• Retrieving the layer ID.

  function getMapLayers() {
    for (var j=0, jl=myMap.layerIds.length; j<jl; j++) {
      var currentLayer = myMap.getLayer(myMap.layerIds[j]);
      alert("id: " + currentLayer.id);
    }
  }
  

var infoTemplates = {
  3: {
    infoTemplate: new InfoTemplate(),
    layerUrl: null
  }
};

var dynamicLayerInfos = usaLayer.createDynamicLayerInfosFromLayerInfos();

var layer = new esri.layers.ArcGISDynamicMapServiceLayer(
        "https://www.example.com/arcgis/rest/services/Petroleum/KSFields/MapServer");
layer.setDisableClientCaching(true);

var dynamicLayerInfos = [];
var dynamicLayerInfo = new esri.layers.DynamicLayerInfo();
dynamicLayerInfo.id = 1;
var dataSource = new esri.layers.QueryDataSource();
dataSource.workspaceId = "d203_db";
dataSource.query = "SELECT * FROM sde.sde.states_geom";

var layerSource = new esri.layers.LayerDataSource();
layerSource.dataSource = dataSource;
dynamicLayerInfo.source = layerSource;
dynamicLayerInfos.push(dynamicLayerInfo);

dynamicData.setDynamicLayerInfos(dynamicLayerInfos);

layer.setGDBVersion("sde.dynamicLayers");

The layerDefinitions argument is an array of layer definition expressions such as in the code snippet below.

var layerDefinitions = [];
layerDefinitions[0] = "POPULATION > 5000000";
layerDefinitions[5] = "AREA > 100000";
dynamicMapServiceLayer.setLayerDefinitions(layerDefinitions);

var layerDrawingOptions = [];
var layerDrawingOption = new esri.layers.LayerDrawingOptions();

layerDrawingOption.renderer = new esri.renderer.SimpleRenderer(mySymbol);

layerDrawingOptions[1] = layerDrawingOption;
dynamicData.setLayerDrawingOptions(layerDrawingOptions);

layer.setOpacity(0.5);

var inputs = dojo.query(".list_item"), input;

visible = [];

for (var i=0, il=inputs.length; i< il; i++) {

  if (inputs[i].checked) {

    visible.push(inputs[i].id);

  }

}

layer.setVisibleLayers(visible);