var serverConnection = new CIMInternetServerConnection { URL = "https://spritle.esri.com/arcgis/services/sanfrancisco_sld/MapServer/WMSServer" };
var connection = new CIMWMSServiceConnection { ServerConnection = serverConnection };
LayerCreationParams parameters = new LayerCreationParams(connection);
parameters.MapMemberPosition = MapMemberPosition.AddToBottom;
await QueuedTask.Run(() =>
{
var compositeLyr = LayerFactory.Instance.CreateLayer<WMSLayer>(parameters, MapView.Active.Map);
//wms layer in ArcGIS Pro always has a composite layer inside it
var wmsLayers = compositeLyr.Layers[0] as ServiceCompositeSubLayer;
//each wms sublayer belongs in that composite layer
var highwayLayerWMSSub = wmsLayers.Layers[1] as WMSSubLayer;
//toggling a sublayer's visibility
if ((highwayLayerWMSSub != null))
{
bool visibility = highwayLayerWMSSub.IsVisible;
highwayLayerWMSSub.SetVisibility(!visibility);
}
//applying an existing style to a wms sub layer
var pizzaLayerWMSSub = wmsLayers.Layers[0] as WMSSubLayer;
var currentStyles = pizzaLayerWMSSub.GetStyleNames();
pizzaLayerWMSSub.SetStyleName(currentStyles[1]);
});