ลองตัวเอง - JavaScript Reference ontimeupdate

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<p>In this example, we use the HTML DOM to assign an "ontimeupdate" event to a video element. When the user starts to play the video, or skips to a new position in the video, a function is triggered, which will display the current position (in seconds) of the video playback.</p>

<video id="myVideo" controls>
  <source src="mov_bbb.mp4" type="video/mp4">
  <source src="mov_bbb.ogg" type="video/ogg">
  Your browser does not support HTML5 video.
</video>

<p>Playback position: <span id="demo"></span></p>

// Assign an ontimeupdate event to the video element, and execute a function if the current playback position has changed
x.ontimeupdate = function() {myFunction()};

function myFunction() {
    // Display the current position of the video in a p element with id="demo"
    document.getElementById("demo").innerHTML = x.currentTime;
}
</script>

<p>Video courtesy of <a href="../../www.bigbuckbunny.org/index.html" target="_blank">Big Buck Bunny</a>.</p>

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