AudioBufferSourceNode.loop - Web APIs 编辑

The loop property of the AudioBufferSourceNode interface is a Boolean indicating if the audio asset must be replayed when the end of the AudioBuffer is reached.

The loop property's default value is false.

Syntax

var loopingEnabled = AudioBufferSourceNode.loop;
AudioBufferSourceNode.loop = true | false;

Value

A Boolean which is true if looping is enabled; otherwise, the value is false.

When looping is enabled, the sound begins playing at the time specified as the start point when start() is called. When the time specified by the loopEnd property is reached, playback continues at the time specified by loopStart

Example

In this example, the AudioContext.decodeAudioData function is used to decode an audio track and put it into an AudioBufferSourceNode. Buttons are provided to play and stop the audio playback, and a slider control is used to change the playbackRate property value on the fly. When the audio is played, it loops.

You can run the full example live (or view the source.)

function getData() {
  source = audioCtx.createBufferSource();
  request = new XMLHttpRequest();

  request.open('GET', 'viper.ogg', true);

  request.responseType = 'arraybuffer';

  request.onload = function() {
    var audioData = request.response;

    audioCtx.decodeAudioData(audioData, function(buffer) {
        myBuffer = buffer;
        source.buffer = myBuffer;
        source.playbackRate.value = playbackControl.value;
        source.connect(audioCtx.destination);
        source.loop = true;
      },

      function(e){"Error with decoding audio data" + e.err});

  }

  request.send();
}

// wire up buttons to stop and play audio, and range slider control

play.onclick = function() {
  getData();
  source.start(0);
  play.setAttribute('disabled', 'disabled');
  playbackControl.removeAttribute('disabled');
}

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• Web Audio API
• Using the Web Audio API
• AudioBufferSourceNode