Rathmath,
If the basemap is in a different spatial reference then the one you need for that map service then you will have to re-project the extent drawn by the end user using the GeometryService.
Here is a quick simple example app:
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no"/>
<title>Simple Map</title>
<link rel="stylesheet" href="http://js.arcgis.com/3.14/esri/css/esri.css">
<style>
html, body, #map {
height: 100%;
width: 100%;
margin: 0;
padding: 0;
}
body {
background-color: #FFF;
overflow: hidden;
font-family: "Trebuchet MS";
}
</style>
<script src="http://js.arcgis.com/3.14/"></script>
<script>
var map, gsvc;
require([
"esri/map",
"esri/tasks/GeometryService",
"esri/tasks/ProjectParameters",
"esri/toolbars/draw",
"esri/graphic",
"esri/layers/ArcGISDynamicMapServiceLayer",
"esri/SpatialReference",
"dojo/_base/lang",
"dojo/on",
"esri/symbols/SimpleFillSymbol",
"dojo/domReady!"
], function(
Map,
GeometryService,
ProjectParameters,
Draw,
Graphic,
ArcGISDynamicMapServiceLayer,
SpatialReference,
lang,
on,
SimpleFillSymbol
) {
map = new Map("map", {
basemap: "topo", //For full list of pre-defined basemaps, navigate to http://arcg.is/1JVo6Wd
center: [-122.45, 37.75], // longitude, latitude
zoom: 13
});
gsvc = new GeometryService("http://sampleserver6.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");
var dLayer = new ArcGISDynamicMapServiceLayer("http://sampleserver5.arcgisonline.com/arcgis/rest/services/911CallsHotspot/MapServer");
map.addLayer(dLayer);
on(map, 'load', createToolbar);
function createToolbar() {
var toolbar = new Draw(map);
toolbar.activate(Draw.EXTENT);
toolbar.on("draw-end", addToMap);
}
function addToMap(evt) {
map.graphics.clear();
evt.target.deactivate();
var graphic = new Graphic(evt.geometry, new SimpleFillSymbol());
console.info("In Geometry: ", evt.geometry.xmax, evt.geometry.xmin, evt.geometry.ymax, evt.geometry.ymin);
map.graphics.add(graphic);
var params = new ProjectParameters();
params.geometries = [evt.geometry];
params.outSR = new SpatialReference({wkid:102726});
gsvc.project(params, lang.hitch(this, function(geomsArr){
console.info("Out Geometry: ", geomsArr[0].xmax, geomsArr[0].xmin, geomsArr[0].ymax, geomsArr[0].ymin);
}));
}
});
</script>
</head>
<body>
<div id="map"></div>
</body>
</html>
