Element: compositionstart event
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.
Thecompositionstart event is fired when a text composition system such as aninput method editor starts a new composition session.
For example, this event could be fired after a user starts entering a Chinese character using aPinyinInput method editor.
Syntax
Use the event name in methods likeaddEventListener(), or set an event handler property.
addEventListener("compositionstart", (event) => { })oncompositionstart = (event) => { }Event type
ACompositionEvent. Inherits fromUIEvent andEvent.
Event properties
This interface also inherits properties of its parent,UIEvent, and its ancestor —Event.
CompositionEvent.dataRead onlyReturns the characters generated by the input method that raised the event; its varies depending on the type of event that generated the
CompositionEventobject.CompositionEvent.localeRead onlyDeprecatedReturns the locale of current input method (for example, the keyboard layout locale if the composition is associated with IME).
Examples
const inputElement = document.querySelector('input[type="text"]');inputElement.addEventListener("compositionstart", (event) => { console.log(`generated characters were: ${event.data}`);});Live example
HTML
<div> <label for="example"> Focus the text-input control, then open your IME and begin typing. </label> <input type="text" name="example" /></div><div> <label for="eventLog">Event log:</label> <textarea readonly rows="8" cols="25" ></textarea> <button>Clear</button></div>body { padding: 0.2rem; display: grid; grid-template-areas: "control log";}.control { grid-area: control;}.event-log { grid-area: log;}.event-log-contents { resize: none;}label,button { display: block;}input[type="text"] { margin: 0.5rem 0;}kbd { border-radius: 3px; padding: 1px 2px 0; border: 1px solid black;}JavaScript
const inputElement = document.querySelector('input[type="text"]');const log = document.querySelector(".event-log-contents");const clearLog = document.querySelector(".clear-log");clearLog.addEventListener("click", () => { log.textContent = "";});function handleEvent(event) { log.textContent += `${event.type}: ${event.data}\n`;}inputElement.addEventListener("compositionstart", handleEvent);inputElement.addEventListener("compositionupdate", handleEvent);inputElement.addEventListener("compositionend", handleEvent);Result
Specifications
| Specification |
|---|
| UI Events # event-type-compositionstart |
Browser compatibility
See also
- Related events:
compositionend,compositionupdate.