ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Desktop.Mapping Namespace / LayerFactory Class / CreateLayer Method / CreateLayer(Uri,ILayerContainerEdit,Int32,String) Method
An URI represents the path or url to a dataset or .lyrx or .lpkx file.
A map or group layer instance where the Layer will be added
The position of the layer in the map or group layer. 0 represents the top most position.
(optional) When it is not provided, the default display name gets used e.g. the dataset name or alias. (default value = "")
Example Version

CreateLayer(Uri,ILayerContainerEdit,Int32,String) Method
Creates a new Layer instance with the specified path to a dataset and adds it to a container such as a map or a group layer. Optionally you can provide a name to override the default display name. This method must be called on the MCT. Use QueuedTask.Run.
Syntax

Parameters

dataUri
An URI represents the path or url to a dataset or .lyrx or .lpkx file.
container
A map or group layer instance where the Layer will be added
index
The position of the layer in the map or group layer. 0 represents the top most position.
layerName
(optional) When it is not provided, the default display name gets used e.g. the dataset name or alias. (default value = "")

Return Value

Exceptions
ExceptionDescription
This method or property must be called within the lambda passed to QueuedTask.Run.
DataUri or conainer is null.
Remarks

Some sample paths to:

A FeatureClass in a FileGeodatabase C:\Data\MyFileGDB.gdb\Census
A shape file in a folder \\Machine\SharedFolder\MySpatialData.dbf
A RasterDataset in a FileGeodatabase C:\Data\MyFileGDB.gdb\DEM
A FeatureClass from a SDE C:\Connections\MySDEConnection.sde\Roads
An image file in a folder \\Machine\SharedFolder\Imagery.tif
A .lyrx or .lpkx file \\Machine\SharedFolder\Fires.lyrx
A map service layer http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Demographics/ESRI_Census_USA/MapServer
A feature layer off a map or feature service http://sampleserver6.arcgisonline.com/arcgis/rest/services/NapervilleShelters/FeatureServer/0

Example
Create and add a layer to the active map
      /*
* string url = @"c:\data\project.gdb\DEM";  //Raster dataset from a FileGeodatabase
* string url = @"c:\connections\mySDEConnection.sde\roads";  //FeatureClass of a SDE
* string url = @"c:\connections\mySDEConnection.sde\States\roads";  //FeatureClass within a FeatureDataset from a SDE
* string url = @"c:\data\roads.shp";  //Shapefile
* string url = @"c:\data\imagery.tif";  //Image from a folder
* string url = @"c:\data\mySDEConnection.sde\roads";  //.lyrx or .lpkx file
* string url = @"c:\data\CAD\Charlottesville\N1W1.dwg\Polyline";  //FeatureClass in a CAD dwg file
* string url = @"C:\data\CAD\UrbanHouse.rvt\Architectural\Windows"; //Features in a Revit file
* string url = @"http://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Demographics/ESRI_Census_USA/MapServer";  //map service
* string url = @"http://sampleserver6.arcgisonline.com/arcgis/rest/services/NapervilleShelters/FeatureServer/0";  //FeatureLayer off a map service or feature service
*/
      string url = @"c:\data\project.gdb\roads";  //FeatureClass of a FileGeodatabase

      Uri uri = new Uri(url);
      await QueuedTask.Run(() => LayerFactory.Instance.CreateLayer(uri, MapView.Active.Map));
Create a raster layer
string url = @"C:\Images\Italy.tif";
await QueuedTask.Run(() =>
{
  // Create a raster layer using a path to an image.
  // Note: You can create a raster layer from a url, project item, or data connection.
  rasterLayer = LayerFactory.Instance.CreateLayer(new Uri(url), aMap) as RasterLayer;
});
Create a mosaic layer
MosaicLayer mosaicLayer = null;
string url = @"C:\Images\countries.gdb\Italy";
await QueuedTask.Run(() =>
{
  // Create a mosaic layer using a path to a mosaic dataset.
  // Note: You can create a mosaic layer from a url, project item, or data connection.
  mosaicLayer = LayerFactory.Instance.CreateLayer(new Uri(url), aMap) as MosaicLayer;
});
Create an image service layer
ImageServiceLayer isLayer = null;
string url =
@"http://imagery.arcgisonline.com/arcgis/services/LandsatGLS/GLS2010_Enhanced/ImageServer";
await QueuedTask.Run(() =>
{
  // Create an image service layer using the url for an image service.
  isLayer = LayerFactory.Instance.CreateLayer(new Uri(url), aMap) as ImageServiceLayer;
});
Create a stream layer with a definition query
//Must be on the QueuedTask
var url = "https://geoeventsample1.esri.com:6443/arcgis/rest/services/AirportTraffics/StreamServer";
var lyrCreateParam = new FeatureLayerCreationParams(new Uri(url))
{
  IsVisible = true,
  //At 2.x - DefinitionFilter = new CIMDefinitionFilter()
  //{
  //  DefinitionExpression = "RWY = '29L'",
  //  Name = "Runway"
  //}
  DefinitionQuery = new DefinitionQuery(whereClause: "RWY = '29L'", name: "Runway")
};

var streamLayer = LayerFactory.Instance.CreateLayer<StreamLayer>(lyrCreateParam, map);
Create a stream layer with a simple renderer
var url = @"https://geoeventsample1.esri.com:6443/arcgis/rest/services/LABus/StreamServer";
var uri = new Uri(url, UriKind.Absolute);
//Must be on QueuedTask!
var createParams = new FeatureLayerCreationParams(uri)
{
  RendererDefinition = new SimpleRendererDefinition()
  {
    SymbolTemplate = SymbolFactory.Instance.ConstructPointSymbol(
                        ColorFactory.Instance.BlueRGB,
                        12,
                 SimpleMarkerStyle.Pushpin).MakeSymbolReference()
  }
};
var streamLayer = LayerFactory.Instance.CreateLayer<StreamLayer>(
                    createParams, map);

Setting a unique value renderer for latest observations
var url = @"https://geoeventsample1.esri.com:6443/arcgis/rest/services/AirportTraffics/StreamServer";
var uri = new Uri(url, UriKind.Absolute);
//Must be on QueuedTask!

var createParams = new FeatureLayerCreationParams(uri)
{
  IsVisible = false
};
var streamLayer = LayerFactory.Instance.CreateLayer<StreamLayer>(
                    createParams, map);
//Define the unique values by hand
var uvr = new CIMUniqueValueRenderer()
{
  Fields = new string[] { "ACTYPE" },
  UseDefaultSymbol = true,
  DefaultLabel = "Others",
  DefaultSymbol = SymbolFactory.Instance.ConstructPointSymbol(
              CIMColor.CreateRGBColor(185, 185, 185), 8, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
};

var classes = new List<CIMUniqueValueClass>();
//add in classes - one for ACTYPE of 727, one for DC 9
classes.Add(
  new CIMUniqueValueClass() {
        Values = new CIMUniqueValue[] {
              new CIMUniqueValue() { FieldValues = new string[] { "B727" } } },
        Visible = true,
        Label = "Boeing 727",
        Symbol = SymbolFactory.Instance.ConstructPointSymbol(
              ColorFactory.Instance.RedRGB, 10, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
});
classes.Add(
  new CIMUniqueValueClass()
  {
    Values = new CIMUniqueValue[] {
              new CIMUniqueValue() { FieldValues = new string[] { "DC9" } } },
    Visible = true,
    Label = "DC 9",
    Symbol = SymbolFactory.Instance.ConstructPointSymbol(
              ColorFactory.Instance.GreenRGB, 10, SimpleMarkerStyle.Hexagon).MakeSymbolReference()
  });
//add the classes to a group
var groups = new List<CIMUniqueValueGroup>()
{
  new CIMUniqueValueGroup() {
     Classes = classes.ToArray()
  }
};
//add the groups to the renderer
uvr.Groups = groups.ToArray();
//Apply the renderer (for current observations)
streamLayer.SetRenderer(uvr);
streamLayer.SetVisibility(true);//turn on the layer
Create Voxel Layer
//Must be on the QueuedTask.Run()

//Must be a .NetCDF file for voxels
var url = @"C:\MyData\AirQuality_Redlands.nc";
var cim_connection = new CIMVoxelDataConnection()
{
    URI = url
};
//Create a VoxelLayerCreationParams
var createParams = VoxelLayerCreationParams.Create(cim_connection);
createParams.IsVisible = true;

//Can also just use the path directly...
//var createParams = VoxelLayerCreationParams.Create(url);

//Use VoxelLayerCreationParams to enumerate the variables within
//the voxel
var variables = createParams.Variables;
foreach (var variable in variables)
{
    var line = $"{variable.Variable}: {variable.DataType}, " +
       $"{variable.Description}, {variable.IsDefault}, {variable.IsSelected}";
    System.Diagnostics.Debug.WriteLine(line);
}
//Optional: set the default variable
createParams.SetDefaultVariable(variables.Last());

//Create the layer - map must be a local scene
VoxelLayer voxelLayer = LayerFactory.Instance.CreateLayer<VoxelLayer>(createParams, map);
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also