Javascript 代码段是否已在上使用

对于OP用于其特定用例的稍加修改的版本，.

帮助未来的答案寻求者，这是检查浏览器/设备是否支持自动播放的理想方法：

var promise = document.getElementById('video').play();

if( typeof promise !== 'undefined' ) {
    promise.then(function() {
        // auto-play started!
    }).catch(function(error) {
        // auto-play failed
    });
}

---

请注意，并非所有浏览器都支持媒体播放承诺。如果浏览器不支持它，它将返回

未定义的
，您能不能在ajax之后显式调用play with jscall@kalpaitch你能？我的印象是，在手机上，用户必须显式播放音频，以避免不必要的带宽使用。试试这个@Zenith，你应该在回答中发布更多信息的链接。我明天要试试，如果行得通，你就可以得到赏金！据我所知，modernizr无法检测到
autoplay
，在modernizr文档中我不认为这是可测试的。我将其实现到我的登录表单中，然后在提交表单时（因为在延迟后检查值时效果最好），然后将自动播放值填充到登录表单中的隐藏字段中。然后，当用户登录时，我可以将值保存到会话中，并在整个体验中记住它，而无需在每个页面上执行此操作。真正的问题是，此脚本在Chrome for mobile上崩溃。值得注意的是，这需要jQuery查询
$（audio）.on（）
位。可能会改用
addEventListener
？
var AUTOPLAY = false; // A flag to be used in the anonymous function

(function() {

    // Audio file data URIs; MP3 + OGG
    var mp3 = 'data:audio/mpeg;base64,/+MYxAAAAANIAUAAAASEEB/jwOFM/0MM/90b/+RhST//w4NFwOjf///PZu////9lns5GFDv//l9GlUIEEIAAAgIg8Ir/JGq3/+MYxDsLIj5QMYcoAP0dv9HIjUcH//yYSg+CIbkGP//8w0bLVjUP///3Z0x5QCAv/yLjwtGKTEFNRTMuOTeqqqqqqqqqqqqq/+MYxEkNmdJkUYc4AKqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq';
    var ogg = 'data:audio/ogg;base64,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';

    try {
        var audio = new Audio(); // Construct new Audio object
        var src = audio.canPlayType('audio/ogg') ? ogg : mp3; // Ternary statement determining the value of the src variable, which will be either ogg or mp3.
        audio.autoplay = true; // Set autoplay to true

        // This event will only be triggered if setting the autoplay attribute to true works.             
        $(audio).on('play', function() {
            AUTOPLAY = true; // Set the global flag to true, indicating we have support.
        });

        audio.src = src; // Set the audio objects src to the value of the src variable.
    } catch(e) {
        console.log('[AUTOPLAY-ERROR]', e);
        // This means we were unsuccessful - this browser doesn't support the autoplay attribute.
    }
})(); // Invoke anonymous function.

var promise = document.getElementById('video').play();

if( typeof promise !== 'undefined' ) {
    promise.then(function() {
        // auto-play started!
    }).catch(function(error) {
        // auto-play failed
    });
}