zh/searchurl/js/beep.js

   1 //data:charset=utf-8,
   2 var audioCtx = new window.AudioContext;
   3 function beep(duration, frequency, volume, type, callback) {
   4     var oscillator = audioCtx.createOscillator();
   5     var gainNode = audioCtx.createGain();
   6
   7     oscillator.connect(gainNode);
   8     gainNode.connect(audioCtx.destination);
   9
  10     if (volume){gainNode.gain.value = volume;}
  11     if (frequency){oscillator.frequency.value = frequency;}
  12     if (type){oscillator.type = type;}
  13     if (callback){oscillator.onended = callback;}
  14
  15     oscillator.start(audioCtx.currentTime);
  16     oscillator.stop(audioCtx.currentTime + ((duration || 500) / 1000));
  17 };
  18 beep();
  19 self.close();