我想我的网页哔哔每当用户超过我的<textarea>的最大字符限制。


当前回答

我用新的音频API写了一个函数来发出哔哔声。

var beep = (function () {
    var ctxClass = window.audioContext ||window.AudioContext || window.AudioContext || window.webkitAudioContext
    var ctx = new ctxClass();
    return function (duration, type, finishedCallback) {

        duration = +duration;

        // Only 0-4 are valid types.
        type = (type % 5) || 0;

        if (typeof finishedCallback != "function") {
            finishedCallback = function () {};
        }

        var osc = ctx.createOscillator();

        osc.type = type;
        //osc.type = "sine";

        osc.connect(ctx.destination);
        if (osc.noteOn) osc.noteOn(0); // old browsers
        if (osc.start) osc.start(); // new browsers

        setTimeout(function () {
            if (osc.noteOff) osc.noteOff(0); // old browsers
            if (osc.stop) osc.stop(); // new browsers
            finishedCallback();
        }, duration);

    };
})();

jsFiddle。

其他回答

您需要从某个地方提供声音文件。以下是来自Scriptaculous的Sound库的代码:

//Default:
<embed style="height:0" id="sound_#{track}_#{id}" src="#{url}" loop="false" autostart="true" hidden="true"/>

//For Gecko:
if(Prototype.Browser.Gecko && navigator.userAgent.indexOf("Win") > 0){
  if(navigator.plugins && $A(navigator.plugins).detect(function(p){ return p.name.indexOf('QuickTime') != -1 }))
    Sound.template = new Template('<object id="sound_#{track}_#{id}" width="0" height="0" type="audio/mpeg" data="#{url}"/>');
  else if(navigator.plugins && $A(navigator.plugins).detect(function(p){ return p.name.indexOf('Windows Media') != -1 }))
    Sound.template = new Template('<object id="sound_#{track}_#{id}" type="application/x-mplayer2" data="#{url}"></object>');
  else if(navigator.plugins && $A(navigator.plugins).detect(function(p){ return p.name.indexOf('RealPlayer') != -1 }))
    Sound.template = new Template('<embed type="audio/x-pn-realaudio-plugin" style="height:0" id="sound_#{track}_#{id}" src="#{url}" loop="false" autostart="true" hidden="true"/>');
  else
    Sound.play = function(){};
} 
function Sound(url, vol, autoplay, loop)
{
    var that = this;

    that.url = (url === undefined) ? "" : url;
    that.vol = (vol === undefined) ? 1.0 : vol;
    that.autoplay = (autoplay === undefined) ? true : autoplay;
    that.loop = (loop === undefined) ? false : loop;
    that.sample = null;

    if(that.url !== "")
    {
        that.sync = function(){
            that.sample.volume = that.vol;
            that.sample.loop = that.loop;
            that.sample.autoplay = that.autoplay;
            setTimeout(function(){ that.sync(); }, 60);
        };

        that.sample = document.createElement("audio");
        that.sample.src = that.url;
        that.sync();

        that.play = function(){
            if(that.sample)
            {
                that.sample.play();
            }
        };

        that.pause = function(){
            if(that.sample)
            {
                that.sample.pause();
            }
        };
    }
}

var test = new Sound("http://mad-hatter.fr/Assets/projects/FreedomWings/Assets/musiques/freedomwings.mp3");
test.play();

http://jsfiddle.net/sv9j638j/

这在JavaScript中是不可能直接实现的。您需要在HTML中嵌入一个简短的WAV文件,然后通过代码播放该文件。

一个例子:

<script>
function PlaySound(soundObj) {
  var sound = document.getElementById(soundObj);
  sound.Play();
}
</script>

<embed src="success.wav" autostart="false" width="0" height="0" id="sound1"
enablejavascript="true">

然后从JavaScript代码中调用它,如下所示:

PlaySound("sound1");

这应该完全是你想要的-你只需要自己找到/创建哔哔声,这应该是微不足道的。

没有跨浏览器的方法来实现这纯javascript。相反,您可以使用一个小的.wav文件,使用嵌入或对象标记播放。

使用CSS,你可以这样做,如果你添加以下样式的标签,但你需要一个wav文件:

<style type="text/css">
        .beep {cue: url("beep.wav") }
</style>

var body=document.getElementByTagName("body");
body.className=body.className + " " + "beep";