Skip To ContentArcGIS for DevelopersSign In Dashboard
require(["esri/layers/support/LabelClass"], function(LabelClass) { /* code goes here */ });
Class: esri/layers/support/LabelClass
Inheritance: LabelClass Accessor
Since: ArcGIS API for JavaScript 4.0

Defines label expressions, symbols, scale ranges, label priorities, and label placement options for labels on a layer.

Known Limitations

Polygon geometries only support always-horizontal labelPlacement.

See also:

Constructors

new LabelClass(properties)
Parameter:
properties Object
optional

See the properties for a list of all the properties that may be passed into the constructor.

Property Overview

Any properties can be set, retrieved or listened to. See the Working with Properties topic.
NameTypeSummaryClass
String

The name of the class.

more details
more detailsAccessor
String

Defines the content of label text for MapImageLayer.

more details
more detailsLabelClass
Object

Defines the content of label text for FeatureLayer.

more details
more detailsLabelClass
String

The position of the label.

more details
more detailsLabelClass
Number

The maximum scale (most zoomed in) at which labels are visible in the view.

more details
more detailsLabelClass
Number

The minimum scale (most zoomed out) at which labels are visible in the view.

more details
more detailsLabelClass
TextSymbol|LabelSymbol3D

Defines the symbol used for rendering the label.

more details
more detailsLabelClass
Boolean

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

more details
more detailsLabelClass
String

A SQL where clause used to determine the features to which the label class should be applied.

more details
more detailsLabelClass

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
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')

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.

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.
  • Polylines only support center-along label placement in 2D MapViews.
Default Value:null
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

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

NameReturn TypeSummaryClass
LabelClass

Creates a deep clone of the LabelClass.

more details
more detailsLabelClass
*

Creates a new instance of this class and initializes it with values from a JSON object generated from a product in the ArcGIS platform.

more details
more detailsLabelClass
Object

Converts an instance of this class to its ArcGIS portal JSON representation.

more details
more detailsLabelClass

Method Details

clone(){LabelClass}

Creates a deep clone of the LabelClass.

Returns:
TypeDescription
LabelClassA 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:
TypeDescription
*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:
TypeDescription
ObjectThe ArcGIS portal JSON representation of an instance of this class.

API Reference search results

NameTypeModule
Loading...