HTMLMediaElement: progress-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.

Das progress-Event wird regelmäßig ausgelöst, während der Browser eine Ressource lädt.

Dieses Event kann nicht abgebrochen werden und es gibt keine Bubbling.

Syntax

Verwenden Sie den Eventnamen in Methoden wie addEventListener() oder setzen Sie eine Event-Handler-Eigenschaft.

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

onprogress = (event) => { }

Event-Typ

Ein generisches Event.

Beispiele

Live-Beispiel

HTML

html

<div class="example">
  <button type="button">Load video</button>
  <video controls width="250"></video>

  <div class="event-log">
    <label for="eventLog">Event log:</label>
    <textarea readonly class="event-log-contents" id="eventLog"></textarea>
  </div>
</div>

.event-log-contents {
  width: 18rem;
  height: 5rem;
  border: 1px solid black;
  margin: 0.2rem;
  padding: 0.2rem;
}

.example {
  display: grid;
  grid-template-areas:
    "button log"
    "video  log";
}

button {
  grid-area: button;
  width: 10rem;
  margin: 0.5rem 0;
}

video {
  grid-area: video;
}

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

.event-log > label {
  display: block;
}

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 += `${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://mdn.github.io/learning-area/html/multimedia-and-embedding/video-and-audio-content/rabbit320.mp4",
    );
    source.setAttribute("type", "video/mp4");

    video.appendChild(source);
  }
});

Ergebnis

Spezifikationen

Specification
HTML # event-media-progress
HTML # handler-onprogress