使用Web Audio的本地文件将mp3作为ArrayBuffer加载

gur*_*umo 2 javascript audio html5 arraybuffer web-audio-api

我希望加载一个mp3本地文件,然后使用库进行处理,我不能使用XMLHttpRequest,然后我使用下一个代码来读取本地mp3文件:

<!DOCTYPE html>
<html>
    <head>
    </head>
    <body onload="carga();">
        <input id="audio_file" type="file" accept="audio/*" />
        <audio id="audio_player" />
        <script>
            function carga() {

                audio_file.onchange = function(){
                var files = this.files;
                console.log(files);
                alert(files);
                var file = URL.createObjectURL(files[0]); 
                console.log(file);
                alert(file);
                audio_player.src = file; 
                audio_player.play();
                                                };
            }
        </script>
    </body>
</html>
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但XMLHttpRequest返回ArrayBuffer,我的代码返回一个FileList,我需要一个ArrayBuffer进行下一次处理,如何将本地mp3文件加载为ArrayBuffer?

Kai*_*ido 8

现代浏览器中,您可以使用a FileReader及其方法readAsArrayBuffer.

  document.querySelector('input').onchange = function(){
      var fileReader  = new FileReader;
      fileReader.onload = function(){
         var arrayBuffer = this.result;
         snippet.log(arrayBuffer);
         snippet.log(arrayBuffer.byteLength);
         }
      fileReader.readAsArrayBuffer(this.files[0]);

      var url = URL.createObjectURL(this.files[0]); 
      audio_player.src = url; 
      audio_player.play();
    };
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<!-- Provides the `snippet` object, see http://meta.stackexchange.com/a/242144/134069 -->
<script src="http://tjcrowder.github.io/simple-snippets-console/snippet.js"></script>
<input id="audio_file" type="file" accept="audio/*" />
<audio id="audio_player" />
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