视频设备:

<script>
  navigator.mediaDevices.enumerateDevices()
    .then(function(devices) {
      var videoDevices = devices.filter(function(device) {
        return device.kind === 'videoinput';
      });

      var videoList = document.getElementById('video-devices');
      videoDevices.forEach(function(device) {
        var li = document.createElement('li');
        li.appendChild(document.createTextNode(device.label));
        videoList.appendChild(li);
      });
    })
    .catch(function(err) {
      console.log(err.name + ': ' + err.message);
    });
</script>