Mastering ArcGIS Server Development with JavaScript
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The map object

Now that we have the components, we need to create an interactive map; let's put them together. We'll start by constructing a map object, which provides the basis and interaction platform that we'll need to work with. The map constructor takes two arguments. The first parameter, either the HTML node or the id string of a node, indicates where we want to put our map. The second parameter of the map constructor is an options object, where we add the configurable options that make our map work as expected:

function (
    Map, ArcGISDynamicMapServiceLayer,
    IdentifyParameters, IdentifyTask, InfoTemplate,
    arrayUtils
  ) {
 var map = new Map("map", {
 basemap: "national-geographic",
 center: [-95, 45],
 zoom: 3
 });
  });

In the preceding code, we're creating a map in the div element with an id of map. In the map, we're adding a basemap, or a background reference map, in the style of National Geographic. We're centering the map at 45°N and 95°W, at a zoom level of three. We'll go into greater depth concerning these configurations in later chapters. If you're using a desktop browser to view the results, you should see the United States, including Alaska, and Hawaii, as in the following image:

The map object

Tip

If you have experience working with Dojo, most element constructors have the options first, followed by the node or the id of the node. This is the reverse of how we construct a map. Remember, order is important.