require(["esri/form/ExpressionInfo"], (ExpressionInfo) => { /* code goes here */ });
import ExpressionInfo from "@arcgis/core/form/ExpressionInfo.js";
esri/form/ExpressionInfo
The ExpressionInfo
class defines the makeup of visibility expressions, required expressions, editable expressions, and value expressions. Visibility expressions are available on field, group, and relationship elements. These elements are contained within a formTemplate
set directly on either a FeatureForm or FeatureLayer.
All of the Arcade expressions referenced above, excluding value expressions, must follow the specification defined in the Form Constraint Profile. This profile may reference field values using the $feature
variable and the expression must return true
or false
.
Value expressions must follow the specification defined in the Form Calculation Profile. It may reference field values within an individual $feature
or in other layers and must return either a date, number, or string value. Once the expression evaluates, the form's field value updates to the expressions' result.
It is required to set the map
property when instantiating a FeatureForm widget
and using expressions that use the $map
variable.
- See also
Constructors
-
Parameterproperties Objectoptional
See the properties for a list of all the properties that may be passed into the constructor.
Property Overview
Name | Type | Summary | Class |
---|---|---|---|
The name of the class. | Accessor | ||
An Arcade expression following the specification defined by the Form Constraint or Form Calculation profiles. | ExpressionInfo | ||
The name of the expression. | ExpressionInfo | ||
Indicates the return type of the Arcade expression. | ExpressionInfo | ||
The title used to describe the value returned by the expression. | ExpressionInfo |
Property Details
-
expression
expression String
-
An Arcade expression following the specification defined by the Form Constraint or Form Calculation profiles. Visibility expressions, required expressions, and editable expressions follow the specification defined in the Form Constraint profile. These expressions may reference field values using the
$feature
profile variable and must return eithertrue
orfalse
.Value expressions adhere to the specification defined in the Form Calculation profile. The available profile variables when working with value expressions extend beyond just
$feature
since it is also possible to access values beyond the individual feature that is being displayed.Example// Sets the visibility of a field in the form template only if the date is within the last 24 hours. expressionInfo.expression = "IIF(DateDiff(Now(), $feature.incident_date, 'hours') < 24)";
-
name
name String
-
The name of the expression. Set this name to the visibility expression, required expression, editable expression, and/or value expression properties of its respective elements.
ExampleexpressionInfo.name = "withinRange";
-
returnType
returnType String
-
Indicates the return type of the Arcade expression. In FeatureForm expressions, the returnType can be
boolean
,date
,number
orstring
. This is dependant upon the type of expression used. For example, visibility expressions, required expressions, and editable expressions only return a boolean, whereas value expressions return eitherdate
,number
, orstring
.Possible Values:"boolean" |"date" |"number" |"string"
-
title
title String
-
The title used to describe the value returned by the expression.
ExampleexpressionInfo.title = "Did the incident occur within the last 24 hours?";
Method Overview
Name | Return Type | Summary | Class |
---|---|---|---|
Adds one or more handles which are to be tied to the lifecycle of the object. | Accessor | ||
Creates a deep clone of the ExpressionInfo class. | ExpressionInfo | ||
* | Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. | ExpressionInfo | |
Returns true if a named group of handles exist. | Accessor | ||
Removes a group of handles owned by the object. | Accessor | ||
Converts an instance of this class to its ArcGIS portal JSON representation. | ExpressionInfo |
Method Details
-
Inherited from Accessor
Since: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, addHandles added at 4.25. -
Adds one or more handles which are to be tied to the lifecycle of the object. The handles will be removed when the object is destroyed.
// Manually manage handles const handle = reactiveUtils.when( () => !view.updating, () => { wkidSelect.disabled = false; }, { once: true } ); this.addHandles(handle); // Destroy the object this.destroy();
ParametershandleOrHandles WatchHandle|WatchHandle[]Handles marked for removal once the object is destroyed.
groupKey *optionalKey identifying the group to which the handles should be added. All the handles in the group can later be removed with Accessor.removeHandles(). If no key is provided the handles are added to a default group.
-
clone
clone(){ExpressionInfo}
-
Creates a deep clone of the ExpressionInfo class.
ReturnsType Description ExpressionInfo A deep clone of the ExpressionInfo instance.
-
Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. 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.Parameterjson ObjectA 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.
ReturnsType Description * Returns a new instance of this class.
-
hasHandles
InheritedMethodhasHandles(groupKey){Boolean}
Inherited from AccessorSince: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, hasHandles added at 4.25. -
Returns true if a named group of handles exist.
ParametergroupKey *optionalA group key.
ReturnsType Description Boolean Returns true
if a named group of handles exist.Example// Remove a named group of handles if they exist. if (obj.hasHandles("watch-view-updates")) { obj.removeHandles("watch-view-updates"); }
-
Inherited from Accessor
Since: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, removeHandles added at 4.25. -
Removes a group of handles owned by the object.
ParametergroupKey *optionalA group key or an array or collection of group keys to remove.
Exampleobj.removeHandles(); // removes handles from default group obj.removeHandles("handle-group"); obj.removeHandles("other-handle-group");
-
toJSON
toJSON(){Object}
-
Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() guide topic for more information.
ReturnsType Description Object The ArcGIS portal JSON representation of an instance of this class.