File System API - boot from local disk to local file system

Currently, there is really little information on this, so I put together an example that brings together:

• Use attribute webkitdirectoryon <input type="file">.
  • This allows the user to select a directory using the appropriate dialog box.
• Using the file system API.
  • , .
• API .
  • API, . <input type="file"> API .

Chrome, webkit, .

http://jsfiddle.net/zLna6/3/

, , , :

var fs,
    err = function(e) {
        throw e;
    };

// request the sandboxed filesystem
webkitRequestFileSystem(
    window.TEMPORARY,
    5 * 1024 * 1024,
    function(_fs) {
        fs = _fs;
    },
    err
);

// when a directory is selected
$(":file").on("change", function() {
    $("ul").empty();

    // the selected files
    var files = this.files;
    if(!files) return;

    // this function copies the file into the sandboxed filesystem
    function save(i) {
        var file = files[i];

        var text = file ? file.name : "Done!";

        // show the filename in the list
        $("<li>").text(text).appendTo("ul");

        if(!file) return;

        // create a sandboxed file
        fs.root.getFile(
            file.name,
            { create: true },
            function(fileEntry) {
                // create a writer that can put data in the file
                fileEntry.createWriter(function(writer) {
                    writer.onwriteend = function() {
                        // when done, continue to the next file
                        save(i + 1);
                    };
                    writer.onerror = err;

                    // this will read the contents of the current file
                    var fr = new FileReader;
                    fr.onloadend = function() {
                        // create a blob as that what the
                        // file writer wants
                        var builder = new WebKitBlobBuilder;
                        builder.append(fr.result);
                        writer.write(builder.getBlob());
                    };
                    fr.onerror = err;
                    fr.readAsArrayBuffer(file);
                }, err);
            }, 
            err
        );
    }

    save(0);
});

$("ul").on("click", "li:not(:last)", function() {
    // get the entry with this filename from the sandboxed filesystem
    fs.root.getFile($(this).text(), {}, function(fileEntry) {
        // get the file from the entry
        fileEntry.file(function(file) {
            // this will read the contents of the sandboxed file
            var fr = new FileReader;
            fr.onloadend = function() {
                // log part of it
                console.log(fr.result.slice(0, 100));
            };
            fr.readAsBinaryString(file);
        });
    }, err);
});