Project Point using ArcGIS API for JavaScript?

Question

I've to project geometry point

Point(1657272, 6100874) with NZTM, WKID: 2193

But, point is shown near Austria, not on NewZealand maps. I've converted above coordinates to geographic, still its not giving correct results. Following is my code:

var mp = esri.geometry.webMercatorToGeographic(new esri.geometry.Point(1657272, 6100874, new esri.SpatialReference({ wkid: 2193 })));

map = new Map("mapDiv", center: [mp.x,mp.y], zoom: 5, basemap: "streets" });

on(map, "load", addGraphic);

function addGraphic() { map.graphics.add(new esri.Graphic(mp, new esri.symbol.SimpleMarkerSymbol().setColor(new dojo.Color([255, 0, 0, 0.5])) ) ) }

Please tell me what's wrong with above code and why it's not projecting point on correct area.

EDITED CODE

var map, gsvc;

require([ "esri/map", "esri/graphic", "esri/symbols/SimpleMarkerSymbol", "esri/tasks/GeometryService", "esri/tasks/ProjectParameters", "esri/SpatialReference", "esri/InfoTemplate", "dojo/dom", "dojo/on", "dojo/domReady!" ], function( Map, Graphic, SimpleMarkerSymbol, GeometryService, ProjectParameters, SpatialReference, InfoTemplate, dom, on ) {

   map = new Map("map", {
      basemap: "streets",
      center: [174.605369, -37.120276],
      zoom: 5
    });

   gsvc = new GeometryService("http://tasks.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");

   on(map, "load", projectToLatLong);

   function projectToLatLong() {
        map.graphics.clear();

        m_mapPoint = [];
        m_mapPoint[0] = new esri.geometry.Point(1657272, 6100874, new esri.SpatialReference({ wkid: 2193 }));
        var outSR = new SpatialReference(3857);

        var symbol = new SimpleMarkerSymbol(SimpleMarkerSymbol.STYLE_CIRCLE, 20,
                      new SimpleLineSymbol(SimpleLineSymbol.STYLE_SOLID,
                          new Color([255, 0, 0]), 2), new Color([0, 0, 0, 0])
                      )          
        var graphic = new Graphic(m_mapPoint, symbol);
        map.graphics.add(graphic);

        var params = new esri.tasks.ProjectParameters();
        // add array of points
        params.geometries = m_mapPoint;
        // Output Spatial Reference in lat/long (wkid 3857 )           
        params.outSR = outSR;
        gsvc.project(params);
    }
  });
</script>

Please check updated code. Still point is not projecting.

Answer 1

From https://developers.arcgis.com/javascript/jsapi/esri.geometry.webmercatorutils-amd.html#webmercatortogeographic:

Translates the given Web Mercator coordinates to Longitude and Latitude. By default the returned longitude is normalized so that it is within -180 and +180.

But your NZTM coordinates are not in webMercator units. You have to convert them from EPSG:2193 to EPSG:3857 to use this function.

Answer 2

In order to reproject non web-mercator coordinates inside a jsapi app, its necessary to call geometryService.project() which sends off a web request to a valid geometry service.

https://developers.arcgis.com/javascript/jsapi/geometryservice-amd.html#project

Answer 3

Its now projecting point. Thanks all of you for your help. Below is the updated code:

var map, gsvc;

  require([
    "esri/map", "esri/graphic", "esri/symbols/SimpleMarkerSymbol","esri/symbols/SimpleLineSymbol", "esri/Color",
    "esri/tasks/GeometryService", "esri/tasks/ProjectParameters",
    "esri/SpatialReference", "esri/InfoTemplate", "dojo/dom", "dojo/on",
    "dojo/domReady!"
  ], function(
    Map, Graphic, SimpleMarkerSymbol, SimpleLineSymbol, Color,
    GeometryService, ProjectParameters,
    SpatialReference, InfoTemplate, dom, on
  ) {         
    map = new Map("map", {
      basemap: "streets",
       center: [174.605369, -37.120276],        
      zoom: 5
    });

    gsvc = new GeometryService("http://tasks.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer");

    on(map, "load", projectToLatLong);

    function projectToLatLong() {
        map.graphics.clear();

        m_mapPoint = [];
        m_mapPoint[0] = new esri.geometry.Point(1657272, 6100874, new esri.SpatialReference({ wkid: 2193 }));
        var outSR = new SpatialReference(3857);     

        var params = new esri.tasks.ProjectParameters();
        // add array of points
        params.geometries = m_mapPoint;
        // Output Spatial Reference in lat/long (wkid 3857 )            
        params.outSR = outSR;
        //gsvc.project(params, callback);
        gsvc.project(params, function callback(m_mapPoint) {
            pt = m_mapPoint[0];               
            var symbol = new SimpleMarkerSymbol(SimpleMarkerSymbol.STYLE_CIRCLE, 20,
                          new SimpleLineSymbol(SimpleLineSymbol.STYLE_SOLID,
                              new Color([255, 0, 0]), 2), new Color([0, 0, 0, 0])
                          );

                var graphic = new esri.Graphic(pt, symbol);                    
                map.graphics.add(graphic);

        });
    }       
  });

Thanks.