Question

我在应用程序中使用需要作为缓冲区数组获取的音频文件。为此，我让用户选择一个文件（using Ionic/Cordova FileChooser Plugin），然后获得一个URL，如：

content://com.android.providers.media.documents/document/audio%3A8431

此后，我将其发送到Cordova Plugin File resolveNativePath函数，并得到如下路径：

file:///storage/emulated/0/Prueba interno/Interno, Teddybär, Dreh Dich Um__320kbps.mp3

在这里，我做我的audioFileInfo对象

audioFileInfo = {name: "Interno, Teddybär, Dreh Dich Um__320kbps.mp3",
                 originalPath: "content://com.android.providers.media.documents/document/audio%3A8431",
                  path: "file:///storage/emulated/0/Prueba interno"}

最后我调用filePlugin.readAsArrayBuffer(audioFileInfo.path, audioFileInfo.name)来获取缓冲区数组。

当文件位于设备内部存储中时，它可以正常工作，但是当文件来自SD卡时，它就无法工作，因为readAsArrayBuffer返回“找不到”。

SD卡：

文件选择器URL

content://com.android.externalstorage.documents/document/3D91-1C14%3AM%C3%BAsica%20Dana%2F1%20-%20Teddyb%C3%A4r%2C%20Teddyb%C3%A4r%2C%20Dreh%20Dich%20Um__320kbps.mp3

resolveNativePath：

file:///sdcard/Música Dana/1 - Teddybär, Teddybär, Dreh Dich Um__320kbps.mp3

audioFileInfo：

audioFileInfo = {
    name :"1 - Teddybär, Teddybär, Dreh Dich Um__320kbps.mp3"
    originalPath : "content://com.android.externalstorage.documents/document/3D91-1C14%3AM%C3%BAsica%20Dana%2F1%20-%20Teddyb%C3%A4r%2C%20Teddyb%C3%A4r%2C%20Dreh%20Dich%20Um__320kbps.mp3",
    path : "file:///sdcard/Música Dana"
}

readAsArrayBuffer：

FileError {code: 1, message: "NOT_FOUND_ERR"}

我尝试了FilePlugins的resolveLocalFilesystemUrl()，并得到了这个Entry对象：

{
    filesystem: {
        name: "content",
        root: {
            filesystem {
                name: "content",
                root: "...."
            }
        },

        fullPath: "/",
        isDirectory: true,
        isFile: false,
        name: "",
        nativeURL: "content://",
    },
    fullPath: "/com.android.externalstorage.documents/document/3D91-1C14:Música Dana/1 - Teddybär, Teddybär, Dreh Dich Um__320kbps.mp3",
    isDirectory: false,
    isFile: true,
    name: "1 - Teddybär, Teddybär, Dreh Dich Um__320kbps.mp3",
    nativeURL: "content://com.android.externalstorage.documents/document/3D91-1C14%3AM%C3%BAsica%20Dana%2F1%20-%20Teddyb%C3%A4r%2C%20Teddyb%C3%A4r%2C%20Dreh%20Dich%20Um__320kbps.mp3",
}

因为我不知道在path函数的第一个参数中用什么作为readAsArrayBuffer。

如果我使用fullPath和name，则会引发编码错误。如果我只是从fullPath中获得不带名称的“路径”，它还会引发编码错误。

有人有类似的经历吗？

Answer 1

我最终用resolveLocalFilesystemUrl返回的信息制作了自己的FileReader来处理文件，请注意，此代码使用Typescript

let entry = await this.filePlugin.resolveLocalFilesystemUrl(audioFileInfo.originalPath);
 let fileEntry: FileEntry = entry as FileEntry;

 console.log("fileEntry", fileEntry);

 let readFilePromise = new Promise < any > (resolve => {
     console.log("getting File from fileEntry");
     // fileEntry.getMetadata(data => {
     //     console.error("metadata", data); 
     // });
     fileEntry.file((file) => {
         console.log("File", file);
         var reader = new FileReader();

         reader.onloadend = () => {
             console.log("Successful file read: ", reader.result);
             resolve(reader.result);
         };

         reader.onprogress = (progressEvent) => {

             let fileUpdateInfo: FileLoadingUpdateInfo = {
                 audioFileInfo: audioFileInfo,
                 total: progressEvent.total,
                 loaded: progressEvent.loaded,
                 percent: parseFloat((progressEvent.loaded * 100 / progressEvent.total).toFixed(2))
             }
             this.updateAudioFileLoadingText$.next(fileUpdateInfo);
         };
         reader.onerror = (e) => {
             console.error("The reader had a problem", e)
             resolve(undefined);
         }
         reader.onabort = (e) => {
             console.error("We aborted...why???", e)
             resolve(undefined);
         }
         console.log("using reader to readAsArrayBuffer ");
         reader.readAsArrayBuffer(file);


     }, (e) => {
         console.error(e)
     });
 });
 let fileBufferArray = await readFilePromise;
 console.log("fileBufferArray", fileBufferArray);

 return fileBufferArray;

使用cordova-plugin-file从Cordova（离子）中的SD卡中读取文件作为阵列

1 个答案: