928f1a076c
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@52706 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
117 lines
3.9 KiB
C
117 lines
3.9 KiB
C
/////////////////////////////////////////////////////////////////////////////
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// Name: filesystem.h
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// Purpose: topic overview
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// Author: wxWidgets team
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// RCS-ID: $Id$
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// Licence: wxWindows license
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/////////////////////////////////////////////////////////////////////////////
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/**
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@page overview_fs wxFileSystem Overview
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The wxHTML library uses a @b virtual file systems mechanism
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similar to the one used in Midnight Commander, Dos Navigator,
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FAR or almost any modern file manager. It allows the user to access
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data stored in archives as if they were ordinary files. On-the-fly
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generated files that exist only in memory are also supported.
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@li @ref overview_fs_classes
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@li @ref overview_fs_locations
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@li @ref overview_fs_combined
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@li @ref overview_fs_wxhtmlfs
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@li @ref overview_fs_init
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<hr>
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@section overview_fs_classes Classes
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Three classes are used in order to provide virtual file systems mechanism:
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@li The wxFSFile class provides information
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about opened file (name, input stream, mime type and anchor).
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@li The wxFileSystem class is the interface.
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Its main methods are ChangePathTo() and OpenFile(). This class
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is most often used by the end user.
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@li The wxFileSystemHandler is the core
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of virtual file systems mechanism. You can derive your own handler and pass
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it to the VFS mechanism. You can derive your own handler and pass it to
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wxFileSystem's AddHandler() method. In the new handler you only need to
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override the OpenFile() and CanOpen() methods.
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@section overview_fs_locations Locations
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Locations (aka filenames aka addresses) are constructed from four parts:
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@li @b protocol - handler can recognize if it is able to open a
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file by checking its protocol. Examples are "http", "file" or "ftp".
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@li <b>right location</b> - is the name of file within the protocol.
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In "http://www.wxwidgets.org/index.html" the right location is "//www.wxwidgets.org/index.html".
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@li @b anchor - an anchor is optional and is usually not present.
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In "index.htm#chapter2" the anchor is "chapter2".
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@li <b>left location</b> - this is usually an empty string.
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It is used by 'local' protocols such as ZIP.
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See Combined Protocols paragraph for details.
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@section overview_fs_combined Combined Protocols
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The left location precedes the protocol in the URL string.
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It is not used by global protocols like HTTP but it becomes handy when nesting
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protocols - for example you may want to access files in a ZIP archive:
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file:archives/cpp_doc.zip#zip:reference/fopen.htm#syntax
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In this example, the protocol is "zip", right location is
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"reference/fopen.htm", anchor is "syntax" and left location
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is "file:archives/cpp_doc.zip".
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There are @b two protocols used in this example: "zip" and "file".
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@section overview_fs_wxhtmlfs File Systems Included in wxHTML
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The following virtual file system handlers are part of wxWidgets so far:
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@li @b wxArchiveFSHandler:
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A handler for archives such as zip
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and tar. Include file is wx/fs_arc.h. URLs examples:
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"archive.zip#zip:filename", "archive.tar.gz#gzip:#tar:filename".
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@li @b wxFilterFSHandler:
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A handler for compression schemes such
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as gzip. Header is wx/fs_filter.h. URLs are in the form, e.g.:
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"document.ps.gz#gzip:".
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@li @b wxInternetFSHandler:
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A handler for accessing documents
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via HTTP or FTP protocols. Include file is wx/fs_inet.h.
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@li @b wxMemoryFSHandler:
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This handler allows you to access
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data stored in memory (such as bitmaps) as if they were regular files.
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See wxMemoryFSHandler for details.
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Include file is wx/fs_mem.h. URL is prefixed with memory:, e.g.
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"memory:myfile.htm"
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In addition, wxFileSystem itself can access local files.
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@section overview_fs_init Initializing file system handlers
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Use wxFileSystem::AddHandler to initialize a handler, for example:
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@code
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#include <wx/fs_mem.h>
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...
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bool MyApp::OnInit()
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{
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wxFileSystem::AddHandler(new wxMemoryFSHandler);
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...
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}
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@endcode
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*/
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