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PDI · Question #200

Which two characteristics are true for Lightning Web Component custom events? Choose 2 answers

The correct answer is B. By default a custom event only propagates to its immediate container and to its immediate child D. Data may be passed in the payload of a custom event using a property called detail. Lightning Web Component custom events can pass data using the detail property, and when configured to propagate, their scope is typically limited to bubbling up to their immediate container.

Submitted by ahmad_uae· Apr 18, 2026User Interface

Question

Which two characteristics are true for Lightning Web Component custom events? Choose 2 answers

Options

  • AData may be passed In the payload of a custom event using a wire decorated properties.
  • BBy default a custom event only propagates to its immediate container and to its immediate child
  • CBy default a custom event only propagates to it's immediate container.
  • DData may be passed in the payload of a custom event using a property called detail.

How the community answered

(34 responses)
  • A
    3% (1)
  • B
    88% (30)
  • C
    9% (3)

Why each option

Lightning Web Component custom events can pass data using the `detail` property, and when configured to propagate, their scope is typically limited to bubbling up to their immediate container.

AData may be passed In the payload of a custom event using a wire decorated properties.

Data may not be passed in the payload of a custom event using `wire` decorated properties; `wire` is used for adapting a Salesforce function to a component's property or function, not for event payloads.

BBy default a custom event only propagates to its immediate container and to its immediate childCorrect

Lightning Web Component custom events, when configured to propagate (e.g., with `bubbles: true`), will typically propagate up the DOM tree to their immediate container, meaning the parent component. Events that are not `composed` are generally confined to the shadow DOM and the immediate host, ensuring a limited scope unless explicitly configured otherwise.

CBy default a custom event only propagates to it's immediate container.

The default behavior for LWC custom events is `bubbles: false` and `composed: false`, meaning they do not propagate beyond the component that dispatches them, making the statement that they propagate to the immediate container by default incorrect.

DData may be passed in the payload of a custom event using a property called detail.Correct

Custom events in Lightning Web Components utilize the `detail` property of the `CustomEvent` object to pass data from the child component that dispatches the event to any parent component that is listening for it, allowing for flexible communication between components.

Concept tested: LWC custom event propagation and data passing

Source: https://developer.salesforce.com/docs/component-library/documentation/en/lwc/lwc.events_create_dispatch

Topics

#LWC Custom Events#Event Propagation#Component Communication#Event Data Payload

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