W3Schools 试用编辑器 - W3Schools 中文教程

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<h2>Fullscreen with JavaScript</h2>
<p>Click on the button to open the video in fullscreen mode.</p>
<button onclick="openFullscreen();">Open Video in Fullscreen Mode</button>
<p><strong>Tip:</strong> Press the "Esc" key to exit full screen.</p>

<video width="100%" controls id="myvideo">
  <source src="rain.mp4" type="video/mp4">
  <source src="rain.ogg" type="video/ogg">
  Your browser does not support the video tag.
</video>

/* Function to open fullscreen mode */
function openFullscreen() {
  /* If fullscreen mode is available, show the element in fullscreen */
  if (
    document.fullscreenEnabled || /* Standard syntax */
    document.webkitFullscreenEnabled || /* Safari */
    document.msFullscreenEnabled /* IE11 */
  ) {
   
    /* Show the element in fullscreen */
    if (elem.requestFullscreen) {
      elem.requestFullscreen(); /* Standard syntax */
    } else if (elem.webkitRequestFullscreen) { /* Safari */
      elem.webkitRequestFullscreen();
    } else if (elem.msRequestFullscreen) { /* IE11 */
      elem.msRequestFullscreen();
    }
  }
}
</script>

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