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web api event

SourceBuffer: updatestart event

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Available in workers

The updatestart event of the SourceBuffer interface signals the beginning of an appendBuffer() or remove() operation. The updating attribute transitions from false to true.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("updatestart", (event) => { })

onupdatestart = (event) => { }

Event type

A generic Event.

Examples

Listening for the updatestart event

const sourceBuffer = source.addSourceBuffer(mimeCodec);
sourceBuffer.addEventListener("updatestart", () => {
  downloadStatus.textContent = "Modifying buffer...";
});
sourceBuffer.addEventListener("updateend", () => {
  downloadStatus.textContent = "Modification complete";
});

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also