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CustomEvent: detail property

Baseline Widely available

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

Note: This feature is available in Web Workers.

The read-only detail property of the CustomEvent interface returns any data passed when initializing the event.

Value

Whatever data the event was initialized with.

Example

// create custom events
const catFound = new CustomEvent("animalfound", {
  detail: {
    name: "cat",
  },
});
const dogFound = new CustomEvent("animalfound", {
  detail: {
    name: "dog",
  },
});

const element = document.createElement("div"); // create a <div> element

// add an appropriate event listener
element.addEventListener("animalfound", (e) => console.log(e.detail.name));

// dispatch the events
element.dispatchEvent(catFound);
element.dispatchEvent(dogFound);

// "cat" and "dog" logged in the console

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
detail 5 12 6 11.6 5 18 6 12 5 1.0 3 5

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/detail