Select multiple layers and export

[Vakhtang_Zubiashvili]

Hi Guys, 

On my map i want to select multiple layers by drawing rectangle and than export selected features fields. i have this code thanks to @BlakeTerhune   (From my previous topic😞

// create a new sketch view model set its layer
        const sketchViewModell = new SketchViewModel({
          view: view,
          layer: polygonGraphicsLayerr
        });
        // Once user is done drawing a rectangle on the map
        // use the rectangle to select features on the map and table
        sketchViewModell.on("create", async (event) => {
          if (event.state === "complete") {
            // this polygon will be used to query features that intersect it
            const geometriess = polygonGraphicsLayerr.graphics.map(function(graphic){
              return graphic.geometry
            });
            const queryGeometry = await geometryEngineAsync.union(geometriess.toArray());
            selectFeatures(queryGeometry);
          }
        });
        // This function is called when user completes drawing a rectangle
        // on the map. Use the rectangle to select features in the layer and table
        function selectFeatures(geometry) {
            // create a query and set its geometry parameter to the
            // rectangle that was drawn on the view
            var query = {
              geometry: geometry,
              outFields: ["*"]
            };
            
            map.allLayers.forEach(layer => {
            // Query all layers data
                layer.queryFeatures(query)
                .then((results) => {
                    // do something with query results
                  console.log(results)
                })
                .catch(errorCallback);
            });
        };

When i draw rectangle in logs i get error:  layer.queryFeatures is not a function;

what i do wrong? What is wrong here and i can not see? Help

[JoelBennett · Accepted solution]

Your code is assuming that all layers in your map are FeatureLayers, but that is unlikely.  You should therefore check the layer type before trying to execute a query on it.  One simple check would be like so:

map.allLayers.forEach(layer => {
	// Query all layers data
	if (typeof layer.queryFeatures == "function") {
		layer.queryFeatures(query).then((results) => {
			// do something with query results
			console.log(results)
		}).catch(errorCallback);
	}
});

[LefterisKoumis]

JoelBennett is correct.

map.allLayers.forEach(layer => {
            // Query all layers data
			if (layer.type === "feature" && layer.visible){
                layer.queryFeatures(query)
                .then((results) => {
                    // do something with query results
                  console.log(results)
                })
                .catch(errorCallback);
				}
            });

[Vakhtang_Zubiashvili]

Thank You guys @JoelBennett @LefterisKoumis , both code works fine, simply checking layer type 😉 Thanks again for help.