public Map Map {get;}

{
  //Zoom map frame to the extent of a single layer.

  //Note: Must be on QueuedTask.Run
  //Reference map and layer
  Map m = mapFrame.Map;
  FeatureLayer lyr = m.FindLayers("GreatLakes").First() as FeatureLayer;

  //Set the map frame extent to all features in the layer
  mapFrame.SetCamera(lyr, false);
}