Manipulating local files

XForms processors are not required to support the file: protocol, but both formsPlayer and the Firefox extension do. The methods applicable to file: will usually be get and put. In formsPlayer, the approach is to prompt the user on any load or save of a local file, since this is obviously a very powerful technique.

In addition to the file: protocol, formsPlayer implements an experimental protocol called cookie:, which allows forms to load and save XML documents locally without the user needing to be prompted. This is deemed safe because the location for the file is only ever going to be in a sub-directory in the user's local store (i.e., home directory). There is therefore no way for a form to get out of this area and load or overwrite system files.

In addition, the URL for the sub-directory is based on the domain of the site being used, so there is also no way for a form from one site to get access to data from other sites (sites can share data across forms, though, which is very useful).

Typical uses are chaining forms together, where the output for one form is the input to the next, or saving state across an application. An example of the latter is illustrated in our Google Desktop app (to be added) which allows you to save searches across sessions.