The loadstart
event is fired when the browser has started to load a resource.
Bubbles | No |
---|---|
Cancelable | No |
Interface | Event |
Event handler property | onloadstart |
Examples
Live example
HTML
<div class="example"> <button type="button">Load video</button> <video controls width="250"></video> <div class="event-log"> <label>Event log:</label> <textarea readonly class="event-log-contents"></textarea> </div> </div>
CSS
.event-log-contents { width: 18rem; height: 5rem; border: 1px solid black; margin: .2rem; padding: .2rem; } .example { display: grid; grid-template-areas: "button log" "video log"; } button { grid-area: button; width: 10rem; margin: .5rem 0; } video { grid-area: video; } .event-log { grid-area: log; } .event-log>label { display: block; }
JS
const loadVideo = document.querySelector('button'); const video = document.querySelector('video'); const eventLog = document.querySelector('.event-log-contents'); let source = null; function handleEvent(event) { eventLog.textContent = eventLog.textContent + `${event.type}\n`; } video.addEventListener('loadstart', handleEvent); video.addEventListener('progress', handleEvent); video.addEventListener('canplay', handleEvent); video.addEventListener('canplaythrough', handleEvent); loadVideo.addEventListener('click', () => { if (source) { document.location.reload(); } else { loadVideo.textContent = "Reset example"; source = document.createElement('source'); source.setAttribute('src', 'https://interactive-examples.mdn.mozilla.net/media/examples/flower.webm'); source.setAttribute('type', 'video/webm'); video.appendChild(source); } });
Result
Specifications
Specification | Status |
---|---|
HTML Living Standard The definition of 'loadstart media event' in that specification. |
Living Standard |
HTML5 The definition of 'loadstart media event' in that specification. |
Recommendation |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
loadstart event | Chrome Full support Yes | Edge Full support ≤79 | Firefox Full support Yes | IE ? | Opera Full support Yes | Safari ? | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support Yes | Opera Android ? | Safari iOS ? | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown