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CustomEvent

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since July 2015.

Note: This feature is available in Web Workers.

The CustomEvent interface can be used to attach custom data to an event generated by an application.

As an alternative to CustomEvent, you can subclass the Event interface to add custom data and behavior.

Note: If used to attempt to communicate between a web extension content script and a web page script, a non-string detail property throws with "Permission denied to access property" in Firefox. To avoid this issue clone the object. See Share objects with page scripts for more information.

Event CustomEvent

In this article

Constructor

CustomEvent()

Creates a new CustomEvent.

Instance properties

This interface inherits properties from its parent, Event.

CustomEvent.detail Read only

Returns any data passed when initializing the event.

Instance methods

This interface inherits methods from its parent, Event.

CustomEvent.initCustomEvent()

Initializes a CustomEvent object. If the event has already been dispatched, this method does nothing.

Specifications

Specification
DOM
# interface-customevent

Browser compatibility

See also

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  1. Document Object Model (DOM)
  2. CustomEvent
  3. Constructor
    1. CustomEvent()
  4. Instance properties
    1. detail
  5. Instance methods
    1. initCustomEvent()
  6. Inheritance
    1. Event
  7. Related pages for DOM
    1. AbortController
    2. AbortSignal
    3. AbstractRange
    4. Attr
    5. CDATASection
    6. CharacterData
    7. Comment
    8. DOMError
    9. DOMException
    10. DOMImplementation
    11. DOMParser
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    13. Document
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    15. DocumentType
    16. Element
    17. Event
    18. EventTarget
    19. HTMLCollection
    20. MutationObserver
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    26. ProcessingInstruction
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    33. XMLDocument
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    35. XPathExpression
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  8. Guides
    1. Anatomy of the DOM
    2. Attribute reflection
    3. Selection and traversal on the DOM tree
    4. Building and updating the DOM tree
    5. Working with events
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