const labelClass = {  // autocasts as new LabelClass()
  symbol: {
    type: "text",  // autocasts as new TextSymbol()
    color: "white",
    haloColor: "blue",
    haloSize: 1,
    font: {  // autocast as new Font()
       family: "Ubuntu Mono",
       size: 14,
       weight: "bold"
     }
  },
  labelPlacement: "above-right",
  labelExpressionInfo: {
    expression: "$feature.Team + TextFormatting.NewLine + $feature.Division"
  },
  maxScale: 0,
  minScale: 25000000,
  where: "Conference = 'AFC'"
};

const labelLayer = new FeatureLayer({
  portalItem: {  // autocasts as new PortalItem()
    id: "7f0bfc7bf67a407d8efebf584f6d956d"
  },
  labelingInfo: [labelClass]
});

Property Overview

Property Details

declaredClass Stringreadonly inherited

Since: ArcGIS API for JavaScript 4.7

The name of the class. The declared class name is formatted as esri.folder.className.

labelExpression String

Defines the content of label text for MapImageLayer. If working with FeatureLayer, use labelExpressionInfo instead.

Attribute values may be included in labels using SQL syntax. To include an attribute value in a label, wrap the name of the field in square brackets []. See the example snippet below.

Default Value:null

Example:

// For Spokane County, WA, label will display: "Spokane County, Washington"
labelClass.labelExpression = '[COUNTY_NAME] CONCAT " County, " CONCAT [STATE_NAME]';

labelExpressionInfo Object

Defines the content of label text for FeatureLayer. If working with MapImageLayer, use labelExpression instead.

Properties:

value String Deprecated since version 4.5. Use expression instead. optional The SQL expression defining the content of the label text.

expression String An Arcade expression that evaluates to a string used to label features in the layer. The most simple expressions return field values. For example, to label a layer of cities with their names, simply reference the field value with the global variable: $feature.CITY_NAME. Expressions can be more sophisticated and use logical functions. This may be useful if you want to use classed labels. For example, the following expression appends city to the end of the label if the feature's population field contains a number greater than 10,000. Otherwise, town is appended to the end of the label. Additionally, you can use TextFormatting.NewLine to add a new line to the label. IIF($feature.POPULATION > 10000, $feature.NAME + ' city', $feature.NAME + ' town')

Default Value:null

Example:

// For Spokane County, WA, label will display: "Spokane County, Washington"
labelClass.labelExpressionInfo = {
  expression: "$feature.COUNTY_NAME + ' County, ' + $feature.STATE_NAME"
};

labelPlacement String

The position of the label. Possible values are based on the feature type. This property requires a value.

Feature Type	Possible Values
Points	above-center, above-left, above-right, below-center, below-left, below-right, center-center, center-left, center-right
Polylines	above-after, above-along, above-before, above-start, above-end, below-after, below-along, below-before, below-start, below-end, center-after, center-along, center-before, center-start, center-end
Polygons	always-horizontal

Known Limitations

• Currently, if the label has a line callout in a 3D SceneView, then only above-center is supported.
• Label placement only applies to Point layers in 3D SceneViews.
• FeatureLayer Polylines only support center-along label placement in 2D MapViews.

Possible Values:"above-center"|"above-left"|"above-right"|"below-center"|"below-left"|"below-right"|"center-center"|"center-left"|"center-right"|"above-after"|"above-along"|"above-before"|"above-start"|"above-end"|"below-after"|"below-along"|"below-before"|"below-start"|"below-end"|"center-after"|"center-along"|"center-before"|"center-start"|"center-end"|"always-horizontal"

Default Value:null

See also:

• Point label placement properties

• Polyline label placement properties

• Polygon label placement properties

Example:

labelClass.labelPlacement = "above-right";

maxScale Number

The maximum scale (most zoomed in) at which labels are visible in the view. A value of 0 means the label's visibility does not have a maximum scale. The maxScale value should always be smaller than the minScale value, and greater than or equal to the service specification.

Default Value:0

minScale Number

The minimum scale (most zoomed out) at which labels are visible in the view. A value of 0 means the label's visibility does not have a minimum scale. The minScale value should always be larger than the maxScale value, and lesser than or equal to the service specification.

Default Value:0

symbol TextSymbol|LabelSymbol3Dautocast

Defines the symbol used for rendering the label. If not set, the default symbol will be used. See the example below.

Example:

// If not set, this default symbol will be used
labelClass.symbol = {
  type: "text",
  color: [255, 255, 255, 255],  // white
  font: { family: "Arial Unicode MS", size: 10, weight: "bold" },
  haloColor: [0, 0, 0, 255],  // black
  haloSize: 1
};

useCodedValues Boolean

Indicates whether to use domain names if the fields in the labelExpression or labelExpressionInfo have domains.

where String

A SQL where clause used to determine the features to which the label class should be applied. When specified, only features evaluating to true based on this expression will be labeled.

Default Value:null

Examples:

labelClass.where = "CITYNAME = 'Redlands'";

labelClass.where = "MARKER_ACTIVITY IN ('Picnicking', 'Group Camping')";

Method Overview

Method Details

clone(){LabelClass}

Creates a deep clone of the LabelClass.

Returns:

Type	Description
LabelClass	A deep clone of the object that invoked this method.

Example:

// Creates a deep clone of the layer's first labelClass
var label = layer.labelingInfo[0].clone();

fromJSON(json){*}static

Creates a new instance of this class and initializes it with values from a JSON object generated from a product in the ArcGIS platform. The object passed into the input json parameter often comes from a response to a query operation in the REST API or a toJSON() method from another ArcGIS product. See the Using fromJSON() topic in the Guide for details and examples of when and how to use this function.

Parameter:

json Object A JSON representation of the instance in the ArcGIS format. See the ArcGIS REST API documentation for examples of the structure of various input JSON objects.

Returns:

Type	Description
*	Returns a new instance of this class.

toJSON(){Object}

Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() topic in the Guide for more information.

Returns:

Type	Description
Object	The ArcGIS portal JSON representation of an instance of this class.