1. Dart
2. dart:html
3. CustomElementRegistry
4. whenDefined method

##### CustomElementRegistry class

1. Properties
2. hashCode
3. runtimeType
4. Methods
5. define
6. get
7. noSuchMethod
8. toString
9. whenDefined
10. Operators
11. operator ==

description

# whenDefined method Null safety

Future whenDefined (

1. String name

)

## Implementation

    Future whenDefined(String name) =>
        promiseToFuture(JS("", "#.whenDefined(#)", this, name));