Test if a value is defined the context, returning true or false.

This can be used to check if a value is available yet in the data context, for example isDefined({a}).

If the value exists but is null then true will still be returned. Consider using isNull if you wish to exclude null as well.

Location

Namespace
Fuse.Reactive
Package
Fuse.Reactive.Expressions 1.11.2

Interface of IsDefined

Inherited from ComputeExpression

Inherited from Expression

Inherited from object

Attached UX Attributes

GlobalKey (attached by Resource) : string ux

The ux:Global attribute creates a global resource that is accessible everywhere in UX markup.

Implemented Interfaces