（Web Audio API）振荡器节点错误：无法多次调用启动 [英] (Web Audio API) Oscillator node error: cannot call start more than once

问题描述

当我启动振荡器时，将其停止，然后重新启动;我收到以下错误：

When I start my oscillator, stop it, and then start it again; I get the following error:

Uncaught InvalidStateError: Failed to execute 'start' on 'OscillatorNode': cannot call start more than once.

显然我可以使用获利来停止 音频，但这让我感到很糟糕。什么是一种更有效的方法来停止振荡器，同时能够再次启动它？

Obviously I could use gain to "stop" the audio but that strikes me as poor practice. What's a more efficient way of stopping the oscillator while being able to start it again?

var ctx = new AudioContext();
var osc = ctx.createOscillator();

osc.frequency.value = 8000;

osc.connect(ctx.destination);

function startOsc(bool) {
    if(bool === undefined) bool = true;

    if(bool === true) {
        osc.start(ctx.currentTime);
    } else {
        osc.stop(ctx.currentTime);
    }
}

$(document).ready(function() {
    $("#start").click(function() {
       startOsc(); 
    });
    $("#stop").click(function() {
       startOsc(false); 
    });
});

当前解决方案（在提问时）： http://jsfiddle.net/xbqbzgt2/2/

Current solution (at time of question): http://jsfiddle.net/xbqbzgt2/2/

最终解决方案： http://jsfiddle.net/xbqbzgt2/3/

Final solution: http://jsfiddle.net/xbqbzgt2/3/

推荐答案

更好的方法是启动一次振荡器节点，并在需要时连接/断开振荡器节点，即：

A better way would be to start the oscillatorNode once and connect/disconnect the oscillatorNode from the graph when needed, ie :

var ctx = new AudioContext();
var osc = ctx.createOscillator();   
osc.frequency.value = 8000;    
osc.start();    
$(document).ready(function() {
    $("#start").click(function() {
         osc.connect(ctx.destination);
    });
    $("#stop").click(function() {
         osc.disconnect(ctx.destination);
    });
});

这是如何在 mute the thermin （mozilla web audio api文档）

This how muting in done in muting the thermin (mozilla web audio api documentation)

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