TaskController: TaskController() constructor

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Note: This feature is available in Web Workers.

The TaskController() constructor creates a new TaskController object, optionally setting the initial priority of its associated signal.

If no priority is set, the signal priority defaults to user-visible

Syntax

new TaskController()
new TaskController(options)

An object with the following properties:

priority Optional: The priority of the signal associated with this TaskController. One of: "user-blocking", "user-visible" (default), "background".

This code shows how to construct a task controller that has a signal with default priority (user-visible).

const controller = new TaskController();

To construct a task controller that has a specific signal priority, pass the priority as a property of the optional argument.

controller2 = new TaskController({ priority: "user-blocking" });

Specification
Prioritized Task Scheduling # dom-taskcontroller-taskcontroller

This page was last modified on ⁨Jun 23, 2025⁩ by MDN contributors.