I'm making a drag-and-drop file upload system for photo gallery uploads. This is my source code handling dropped files. This one works multiple files if I drop them one by one it works but when I drop more than one at the same time this error occures:

Uncaught InvalidStateError: Failed to execute 'readAsDataURL' on 'FileReader': The object is already busy reading Blobs.

function handleFiles(files)

{

    var reader = new FileReader();

    var formdata = new FormData();



    $.each(files, function(i, j)

    {

        $(td.photos span.status).html(Processing file: +j.name);



        formdata.append('file', j);



        $.ajax({

            url: uploadalbum.php,

            type: POST,

            dataType: json,

            data: formdata,

            processData: false,

            contentType: false,

            success: uploadfinished

        });



        reader.onload = handleReaderLoad;

        reader.readAsDataURL(j);

    });

}

Any ideas?