HTMLMediaElement: progress event

progress 事件在浏览器加载一个资源的时候周期性触发

Bubbles No
Cancelable No
Interface Event
Event handler property onprogress

示例

在线示例

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>

JavaScript

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);
    }
});

结果

规范

规范 状态
HTML Living Standard
progress media event
Living Standard
HTML5
progress media event
Recommendation

浏览器兼容性

BCD tables only load in the browser

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