日期:2014-05-16 浏览次数:20643 次
<!DOCTYPE html> <html> <head> <title>Audio playbackRate Example</title> </head> <body> <div> <audio id="audio1" style="width:25%" controls>Canvas not supported</audio> </div> <div> <input type="text" id="audioFile" value="audio.mp3" size="60" /> </div> <button id="playbutton" onclick="togglePlay();">Play</button> <button onclick="increaseSpeed();">Increase speed</button> <button onclick="decreaseSpeed();">Decrease speed</button><br /> <div id="rate"></div> <script type="text/javascript"> // Create a couple of global variables to use. var audioElm = document.getElementById("audio1"); // Audio element var ratedisplay = document.getElementById("rate"); // Rate display area // Hook the ratechange event and display the current playbackRate after each change audioElm.addEventListener("ratechange", function () { ratedisplay.innerHTML = "Rate: " + audioElm.playbackRate; }, false); // Alternates between play and pause based on the value of the paused property function togglePlay() { if (document.getElementById("audio1")) { if (audioElm.paused == true) { playAudio(audioElm); // if player is paused, then play the file } else { pauseAudio(audioElm); // if player is playing, then pause } } } function playAudio(audioElm) { document.getElementById("playbutton").innerHTML = "Pause"; // Set button text == Pause // Get file from text box and assign it to the source of the audio element audioElm.src = document.getElementById('audioFile').value; audioElm.play(); } function pauseAudio(audioElm) { document.getElementById("playbutton").innerHTML = "play"; // Set button text == Play audioElm.pause(); } // Increment playbackRate by 1 function increaseSpeed() { audioElm.playbackRate += 1; } // Cut playback rate in half function decreaseSpeed() { if (audioElm.playbackRate <= 1) { var temp = audioElm.playbackRate; audioElm.playbackRate = (temp / 2); } else { audioElm.playbackRate -= 1; } } </script> </body> </html>
https://developer.mozilla.org/zh-CN/docs/Using_HTML5_audio_and_video