How to find the polygon containing a given coordinate using ArcGIS Geometry Service?

Question

Say I have an ArcGIS Server GeometryService running, and a map service containing ZIP code polygons (all ArcGIS 10.1).

I want to pass a coordinate, and have it return which ZIP code contains that coordinate. There seem to be many ways to approach "does THIS point fall within THIS polygon?", but how would I find out which polygon among them all contains a point?

In other words, there's this example where, given two points and a polygon, it will return which of the points is contained by the polygon. But what if you only know the point, and the objective is to determine which polygon?

Answer 1

It looks like either the Query or the Identify tasks will do the trick.

I successfully adapted this sample to prototype this functionality using the ArcGIS JavaScript API:

 var qt1="http://localhost:6080/arcgis/rest/services/simple_ny_outline/MapServer/0"
    var queryTask = new esri.tasks.QueryTask(qt1);
    var query = new esri.tasks.Query();
    query.returnGeometry = true;
    query.outFields = ["*"];
    query.outSpatialReference = {"wkid":26918};


    var currentClick = null;
    dojo.connect(map, "onClick", function(evt) {
      map.graphics.clear();
      currentClick = query.geometry = evt.mapPoint;
      query.spatialRelationship = esri.tasks.Query.SPATIAL_REL_INTERSECTS;
      queryTask.execute(query);
      dojo.byId('messages').innerHTML = "<b>Executing Point Intersection Query...</b>";
    });

    var firstGraphic = null;

    dojo.connect(queryTask, "onComplete", function(graphics) {
      firstGraphic = graphics.features[0];

      console.log(firstGraphic.attributes.COUNTY);
      dojo.byId('messages').innerHTML = "<b>" + firstGraphic.attributes.COUNTY +"</b>";
    });