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web api event

Element: compositionupdate event

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The compositionupdate event is fired when a new character is received in the context of a text composition session controlled by a text composition system such as an input method editor.

For example, this event could be fired while a user enters a Chinese character using a Pinyin Input method editor.

Syntax

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

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

oncompositionupdate = (event) => { }

Event type

A CompositionEvent. Inherits from UIEvent and Event.

Examples

const inputElement = document.querySelector('input[type="text"]');

inputElement.addEventListener("compositionupdate", (event) => {
  console.log(`generated characters were: ${event.data}`);
});

Live example

HTML

<div class="control">
  <p>First select textbox, then to open IME:</p>
  <ul>
    <li>on macOS type <kbd>option</kbd> + <kbd>`</kbd></li>
    <li>on Windows type <kbd>windows</kbd> + <kbd>.</kbd></li>
  </ul>
  <label for="example">Example input</label>
  <input type="text" id="example" name="example" />
</div>

<div class="event-log">
  <label for="eventLog">Event log:</label>
  <textarea
    readonly
    class="event-log-contents"
    rows="8"
    cols="25"
    id="eventLog"></textarea>
  <button class="clear-log">Clear</button>
</div>
body {
  padding: 0.2rem;
  display: grid;
  grid-template-areas: "control log";
}

.control {
  grid-area: control;
}

.event-log {
  grid-area: log;
}

.event-log-contents {
  resize: none;
}

label,
button {
  display: block;
}

input[type="text"] {
  margin: 0.5rem 0;
}

kbd {
  border-radius: 3px;
  padding: 1px 2px 0;
  border: 1px solid black;
}

JavaScript

const inputElement = document.querySelector('input[type="text"]');
const log = document.querySelector(".event-log-contents");
const clearLog = document.querySelector(".clear-log");

clearLog.addEventListener("click", () => {
  log.textContent = "";
});

function handleEvent(event) {
  log.textContent += `${event.type}: ${event.data}\n`;
}

inputElement.addEventListener("compositionstart", handleEvent);
inputElement.addEventListener("compositionupdate", handleEvent);
inputElement.addEventListener("compositionend", handleEvent);

Result

Interactive exampleOpen the canonical MDN source to run this embedded demo.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also