wxFileSystem Class Reference
[Virtual File System]

#include <wx/filesys.h>

Inheritance diagram for wxFileSystem:

wxObject

List of all members.


Detailed Description

This class provides an interface for opening files on different file systems. It can handle absolute and/or local filenames.

It uses a system of handlers (see wxFileSystemHandler) to provide access to user-defined virtual file systems.

Library:  wxBase

Category:  Virtual File System

See also:
wxFileSystemHandler, wxFSFile, wxFileSystem Overview

Public Member Functions

 wxFileSystem ()
void ChangePathTo (const wxString &location, bool is_dir=false)
bool FindFileInPath (wxString str, const wxString &path, const wxString &file)
wxString FindFirst (const wxString &wildcard, int flags=0)
wxString FindNext ()
wxString GetPath () const
wxFSFileOpenFile (const wxString &location, int flags=wxFS_READ)

Static Public Member Functions

static void AddHandler (wxFileSystemHandler handler)
static wxString FileNameToURL (const wxFileName &filename)
static bool HasHandlerForPath (const wxString &location)
static wxFileName URLToFileName (const wxString &url)

Constructor & Destructor Documentation

wxFileSystem::wxFileSystem (  ) 

Constructor.


Member Function Documentation

static void wxFileSystem::AddHandler ( wxFileSystemHandler  handler  )  [static]

This static function adds new handler into the list of handlers (see wxFileSystemHandler) which provide access to virtual FS.

Note that if two handlers for the same protocol are added, the last added one takes precedence.

Note:
You can call:
              wxFileSystem::AddHandler(new My_FS_Handler);
This is because (a) AddHandler is a static method, and (b) the handlers are deleted in wxFileSystem's destructor so that you don't have to care about it.

void wxFileSystem::ChangePathTo ( const wxString location,
bool  is_dir = false 
)

Sets the current location. location parameter passed to OpenFile() is relative to this path.

Remarks:
Unless is_dir is true the location parameter is not the directory name but the name of the file in this directory.
All these commands change the path to "dir/subdir/":

        ChangePathTo("dir/subdir/xh.htm");
        ChangePathTo("dir/subdir", true);
        ChangePathTo("dir/subdir/", true);

Example:

        f = fs->OpenFile("hello.htm"); // opens file 'hello.htm'
        fs->ChangePathTo("subdir/folder", true);
        f = fs->OpenFile("hello.htm"); // opens file 'subdir/folder/hello.htm' !!

Parameters:
location the new location. Its meaning depends on the value of is_dir
is_dir if true location is new directory. If false (the default) location is file in the new directory.

static wxString wxFileSystem::FileNameToURL ( const wxFileName filename  )  [static]

Converts a wxFileName into an URL.

See also:
URLToFileName(), wxFileName

bool wxFileSystem::FindFileInPath ( wxString  str,
const wxString path,
const wxString file 
)

Looks for the file with the given name file in a colon or semi-colon (depending on the current platform) separated list of directories in path.

If the file is found in any directory, returns true and the full path of the file in str, otherwise returns false and doesn't modify str.

Parameters:
str Receives the full path of the file, must not be NULL
path wxPATH_SEP-separated list of directories
file the name of the file to look for

wxString wxFileSystem::FindFirst ( const wxString wildcard,
int  flags = 0 
)

Works like wxFindFirstFile().

Returns the name of the first filename (within filesystem's current path) that matches wildcard.

Parameters:
wildcard The wildcard that the filename must match
flags One of wxFILE (only files), wxDIR (only directories) or 0 (both).

wxString wxFileSystem::FindNext (  ) 

Returns the next filename that matches the parameters passed to FindFirst().

wxString wxFileSystem::GetPath (  )  const

Returns the actual path (set by wxFileSystem::ChangePathTo).

static bool wxFileSystem::HasHandlerForPath ( const wxString location  )  [static]

This static function returns true if there is a registered handler which can open the given location.

wxFSFile* wxFileSystem::OpenFile ( const wxString location,
int  flags = wxFS_READ 
)

Opens the file and returns a pointer to a wxFSFile object or NULL if failed.

It first tries to open the file in relative scope (based on value passed to ChangePathTo() method) and then as an absolute path.

Note that the user is responsible for deleting the returned wxFSFile. flags can be one or more of the wxFileSystemOpenFlags values combined together.

A stream opened with just the default wxFS_READ flag may or may not be seekable depending on the underlying source.

Passing "wxFS_READ | wxFS_SEEKABLE" for flags will back a stream that is not natively seekable with memory or a file and return a stream that is always seekable.

static wxFileName wxFileSystem::URLToFileName ( const wxString url  )  [static]

Converts URL into a well-formed filename. The URL must use the file protocol.



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