Property Overview

Property Details

declaredClassStringreadonly inherited

Since: ArcGIS API for JavaScript 4.7

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

labelExpressionString

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.

Example:

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

labelExpressionInfoObject

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

Properties:

value String optional The SQL expression defining the content of the label text. Deprecated as of v4.5. Use expression instead.

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')

Example:

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

labelPlacementString

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

Possible Values (Points): above-center | above-left | above-right | below-center | below-left | below-right | center-center | center-left | center-right

Possible Values (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

Possible Values (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.
• FeatureLayers only support labeling for Point and Polygon geometries rendered with WebGL.

Default Value:null

Example:

labelClass.labelPlacement = "above-right";

maxScaleNumber

The maximum scale to show labels. The value of maxScale should always be less than the value of minScale. If the value is 0, then the label's visibility isn't dependent on maximum scale.

Default Value:0

minScaleNumber

The minimum scale to show labels. The value of minScale should always be greater than the value of maxScale. If the value of this property is 0, then the visibility of labels isn't dependent on minimum scale.

Default Value:0

symbolTextSymbol|LabelSymbol3Dautocast

Defines the symbol used for rendering the label.

Example:

labelClass.symbol = {
  type: "label-3d",  // autocasts as new LabelSymbol3D()
  symbolLayers: [{
    type: "text",  // autocasts as new TextSymbol3DLayer()
    material: { color: "black" },
    size: 15
  }]
};

useCodedValuesBoolean

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

whereString

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.

Known Limitations

Only very basic SQL is currently supported.

Example:

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

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 graphic's first symbol layer
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.