This page tests possible ways of copying file data between a web page and a local system without server interaction. This is part of HTML5 revolution.

read

Read local file using File API. [File API (draft)] Latest draft specifies FileReader object. [FileReader MDC] Earlier Firefoxes support reading file directly. [File MDC]

Works on Firefox 3+, soon in Chrome.

Show open dialog from javascript:

Firefox does not support click() method on input[type=file] [Mozilla bug 36619], nor label for click routing (they call it insecure, but don't understand why). Same in Opera. Well known opacity:0 hack must be used: [quirksmode.org, Styling an input type="file"]
open file

    write

    There is draft that defines FileWriter [File API: Writer (draft)] but it is not supported yet.

    Currently Data URI [RFC 2397] can be used to save a file: Save hello.zip.

    Problem 1: No way to specify filename.

    Problem 2: No way to force saving. View is the default.

    Doesn't work in Chrome.

    Can be initiated from javascript by assigning location.href property:

      drop

      Dragging file to the page. [whatwg.org, HTML5, Drag and Drop]
      Works on Firefox 3.5
      No browser supports dragging file from a page, AFAIK.
        ✻ ✻ ✻
        Your browser:
        ~jb