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• 句法
• 范例
• Reduced time precision
• 规范
• 浏览器兼容性
• 另请参阅：
• 相关话题

currentTime 只读特性在 BaseAudioContext interface returns a double representing an ever-increasing hardware timestamp in seconds that can be used for scheduling audio playback, visualizing timelines, etc. It starts at 0.

句法

var curTime = baseAudioContext.currentTime;
					

范例

var AudioContext = window.AudioContext || window.webkitAudioContext;
var audioCtx = new AudioContext();
// Older webkit/blink browsers require a prefix
...
console.log(audioCtx.currentTime);
					

Reduced time precision

To offer protection against timing attacks and fingerprinting, the precision of audioCtx.currentTime might get rounded depending on browser settings.
In Firefox, the privacy.reduceTimerPrecision preference is enabled by default and defaults to 20us in Firefox 59; in 60 it will be 2ms.

// reduced time precision (2ms) in Firefox 60
audioCtx.currentTime;
// 23.404
// 24.192
// 25.514
// ...
// reduced time precision with `privacy.resistFingerprinting` enabled
audioCtx.currentTime;
// 49.8
// 50.6
// 51.7
// ...
					

In Firefox, you can also enabled privacy.resistFingerprinting , the precision will be 100ms or the value of privacy.resistFingerprinting.reduceTimerPrecision.microseconds , whichever is larger.

规范

规范	状态	注释
Web 音频 API The definition of 'currentTime' in that specification.	工作草案	初始定义。

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
currentTime	Chrome 10 Prefixed 10 Prefixed Prefixed Implemented with the vendor prefix: webkit	Edge ≤18	Firefox 53 53 注意事项 注意事项 Originally implemented on AudioContext in Firefox 25.	IE 不支持 No	Opera 22 22 15 Prefixed Prefixed Implemented with the vendor prefix: webkit	Safari 6 Prefixed 6 Prefixed Prefixed Implemented with the vendor prefix: webkit	WebView Android Yes	Chrome Android 33	Firefox Android 53 53 注意事项 注意事项 Originally implemented on AudioContext in Firefox Android 26.	Opera Android 22 22 14 Prefixed Prefixed Implemented with the vendor prefix: webkit	Safari iOS 6 Prefixed 6 Prefixed Prefixed Implemented with the vendor prefix: webkit	Samsung Internet Android 2.0

图例

完整支持

完整支持

不支持

不支持

见实现注意事项。

见实现注意事项。

要求使用供应商前缀或不同名称。

要求使用供应商前缀或不同名称。

另请参阅：

• Using Web Audio API

元数据

• 最后修改： 2019 年 3 月 23 日

相关话题

1. Web 音频 API
2. BaseAudioContext
3. 特性

   1. audioWorklet
   2. currentTime
   3. destination
   4. listener
   5. sampleRate
   6. state
4. 方法

   1. createAnalyser()
   2. createBiquadFilter()
   3. createBuffer()
   4. createBufferSource()
   5. createChannelMerger()
   6. createChannelSplitter()
   7. createConstantSource()
   8. createConvolver()
   9. createDelay()
   10. createDynamicsCompressor()
   11. createGain()
   12. createIIRFilter()
   13. createOscillator()
   14. createPanner()
   15. createPeriodicWave()
   16. createScriptProcessor()
   17. createStereoPanner()
   18. createWaveShaper()
   19. decodeAudioData()
5. 继承：

   1. EventTarget
6. Related pages for Web Audio API

   1. AnalyserNode
   2. AudioBuffer
   3. AudioBufferSourceNode
   4. AudioContext
   5. AudioContextOptions
   6. AudioDestinationNode
   7. AudioListener
   8. AudioNode
   9. AudioNodeOptions
   10. AudioParam
   11. AudioProcessingEvent
   12. AudioScheduledSourceNode
   13. AudioWorklet
   14. AudioWorkletGlobalScope
   15. AudioWorkletNode
   16. AudioWorkletProcessor
   17. BiquadFilterNode
   18. ChannelMergerNode
   19. ChannelSplitterNode
   20. ConstantSourceNode
   21. ConvolverNode
   22. DelayNode
   23. DynamicsCompressorNode
   24. GainNode
   25. IIRFilterNode
   26. MediaElementAudioSourceNode
   27. MediaStreamAudioDestinationNode
   28. MediaStreamAudioSourceNode
   29. OfflineAudioCompletionEvent
   30. OfflineAudioContext
   31. OscillatorNode
   32. PannerNode
   33. PeriodicWave
   34. StereoPannerNode
   35. WaveShaperNode