private async void Initialize()
{
_markerSymbol = layoutGrid.Resources["markerSymbol"] as Symbol;
_pointFeatureOverlay = MyMapView.GraphicsOverlays["pointFeatureOverlay"];
// City Layer
FeatureLayer cityLayer = new FeatureLayer(new Uri("https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer/0"));
// State Layer
FeatureLayer stateLayer = new FeatureLayer(new Uri("https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer/2"));
MyMap.OperationalLayers.Add(cityLayer);
MyMap.OperationalLayers.Add(stateLayer);
// State Query
QueryParameters stateQueryParameters = new QueryParameters();
// only select one polygon from State layer
stateQueryParameters.WhereClause = "state_name = 'California'";
// Query the State feature table
FeatureQueryResult stateQueryResult = await stateLayer.FeatureTable.QueryFeaturesAsync(stateQueryParameters);
var stateResult = stateQueryResult.ToList();
// City Query
QueryParameters cityQueryParameter = new QueryParameters();
cityQueryParameter.WhereClause = "1=1";
// Query the City feature table
FeatureQueryResult cityQueryResult = await cityLayer.FeatureTable.QueryFeaturesAsync(cityQueryParameter);
var cities = cityQueryResult.Select(feature => feature.Geometry);
var city_name = cityQueryResult.Select(feature => feature.Attributes);
var citiesWithinState = cities
.Select(city => GeometryEngine.Intersection(city, stateResult[0].Geometry))
.Select(city => new Graphic(city, _markerSymbol));
foreach (Graphic g in citiesWithinState)
{
_pointFeatureOverlay.Graphics.Add(g);
}
}
private async Task <List <Geometry> > QueryLineGeometry(string lineKey)
{
string transmissionDataMapServer = LightningDataSettings.TransmissionDataMapServer;
QueryParameters lineQuery = new QueryParameters();
lineQuery.ReturnGeometry = true;
lineQuery.WhereClause = $"UPPER(LINENAME) LIKE '%{lineKey.ToUpper()}%'";
ServiceFeatureTable featureTable = new ServiceFeatureTable(new Uri(transmissionDataMapServer));
FeatureQueryResult result = await featureTable.QueryFeaturesAsync(lineQuery);
return(result
.Select(feature => feature.Geometry)
.ToList());
}
