JavaScript · Middle · Question 65 of 75

How do you notify other parts of the page about something with a DOM event?

el.dispatchEvent(new CustomEvent("cart:add", { detail: { id: 7 }, bubbles: true }));

✓Correct answer: Dispatch a CustomEvent with data in detail; listeners use addEventListener
2Call el.click() with arguments
3Custom events require a library

Explanation

Set bubbles: true if ancestors should hear it. It is a lightweight way for web components and widgets to communicate without global state.

Further reading

MDN: CustomEvent ↗

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