Get object URL from FileEntry (or equivalent)

blob, file-upload, javascript

Solution

How I fixed it:

from an entry with typeof `FileEntry`, we can just do `.file(callback)`, where the first parameter in the callback is of type `File`, which we can then just create an objectURL from:

var reader = entry.createReader();
reader.readEntries(function (res) {
    res.forEach(function (entry) {
        entry.file(function(file){ //this does the trick
            var obj = URL.createObjectURL(file);
        }
    });
});

Many thanks to dandavis who provided me his javascript code and the approximate line so I could go look for it myself ;)

Problem

I am currently loading dropped files by doing: ``` var files = e.dataTransfer.items; for (var i = 0; i < files.length; i++) { var file = files[i]; //typeof is 'DataTransferItem' var url = URL.createObjectURL(file); } ``` This gets me the object url, which I can then put into a music player. However, when iterating over an inputted folder: ``` var reader = entry.createReader(); reader.readEntries(function (res) { res.forEach(function (entry) { console.log('The entry:', entry); console.log('The url:', JSON.stringify(entry.toURL())); }); }); ``` I get files of type `FileEntry`. According to this I shall be able to do `file.toURL()` and use that instead of an object url. This does return me an empty string. this seems to be there for a reason, but I have no idea how to fix this. I see something about a blob URL but I have no idea how that would work. Example Try to drag files and folders to the output screen and see it yourself

Original source