async public Task <List <IDatasetElement> > Elements()
{
if (_layers != null)
{
return(_layers);
}
List <IDatasetElement> layers = new List <IDatasetElement>();
foreach (var collectionItem in await _spatialCollectionRef.Find <Json.SpatialCollectionItem>(_ => true).ToListAsync())
{
layers.Add(new DatasetElement(await MongoDbFeatureClass.Create(this, collectionItem)));
}
_layers = layers;
return(_layers);
}
async public Task <IDatasetElement> Element(string title)
{
try
{
var collectionItem = await _spatialCollectionRef
.Find <Json.SpatialCollectionItem>(c => c.Name == title)
.FirstOrDefaultAsync();
if (collectionItem == null)
{
return(null);
}
return(new DatasetElement(await MongoDbFeatureClass.Create(this, collectionItem))
{
Title = collectionItem.Name
});
}
catch (Exception ex)
{
this.lastException = ex;
return(null);
}
}