Version: 3.1.1
wxFileSystemHandler Class Referenceabstract

#include <wx/filesys.h>

+ Inheritance diagram for wxFileSystemHandler:

Detailed Description

Classes derived from wxFileSystemHandler are used to access virtual file systems.

Its public interface consists of two methods: wxFileSystemHandler::CanOpen and wxFileSystemHandler::OpenFile.

It provides additional protected methods to simplify the process of opening the file: GetProtocol(), GetLeftLocation(), GetRightLocation(), GetAnchor(), GetMimeTypeFromExt().

Please have a look at overview (see wxFileSystem) if you don't know how locations are constructed.

Also consult the list of available handlers.

Note that the handlers are shared by all instances of wxFileSystem.

Remarks
wxHTML library provides handlers for local files and HTTP or FTP protocol.
Note
The location parameter passed to OpenFile() or CanOpen() methods is always an absolute path. You don't need to check the FS's current path.

wxPerl Note: In wxPerl, you need to derive your file system handler class from Wx::PlFileSystemHandler.

Library:  wxBase
Category:  Virtual File System
See also
wxFileSystem, wxFSFile, wxFileSystem Overview

Public Member Functions

 wxFileSystemHandler ()
 Constructor. More...
 
virtual bool CanOpen (const wxString &location)=0
 Returns true if the handler is able to open this file. More...
 
virtual wxString FindFirst (const wxString &wildcard, int flags=0)
 Works like wxFindFirstFile(). More...
 
virtual wxString FindNext ()
 Returns next filename that matches parameters passed to wxFileSystem::FindFirst. More...
 
virtual wxFSFileOpenFile (wxFileSystem &fs, const wxString &location)=0
 Opens the file and returns wxFSFile pointer or NULL if failed. More...
 
- Public Member Functions inherited from wxObject
 wxObject ()
 Default ctor; initializes to NULL the internal reference data. More...
 
 wxObject (const wxObject &other)
 Copy ctor. More...
 
virtual ~wxObject ()
 Destructor. More...
 
virtual wxClassInfoGetClassInfo () const
 This virtual function is redefined for every class that requires run-time type information, when using the wxDECLARE_CLASS macro (or similar). More...
 
wxObjectRefDataGetRefData () const
 Returns the wxObject::m_refData pointer, i.e. the data referenced by this object. More...
 
bool IsKindOf (const wxClassInfo *info) const
 Determines whether this class is a subclass of (or the same class as) the given class. More...
 
bool IsSameAs (const wxObject &obj) const
 Returns true if this object has the same data pointer as obj. More...
 
void Ref (const wxObject &clone)
 Makes this object refer to the data in clone. More...
 
void SetRefData (wxObjectRefData *data)
 Sets the wxObject::m_refData pointer. More...
 
void UnRef ()
 Decrements the reference count in the associated data, and if it is zero, deletes the data. More...
 
void UnShare ()
 This is the same of AllocExclusive() but this method is public. More...
 
void operator delete (void *buf)
 The delete operator is defined for debugging versions of the library only, when the identifier WXDEBUG is defined. More...
 
void * operator new (size_t size, const wxString &filename=NULL, int lineNum=0)
 The new operator is defined for debugging versions of the library only, when the identifier WXDEBUG is defined. More...
 

Static Public Member Functions

static wxString GetMimeTypeFromExt (const wxString &location)
 Returns the MIME type based on extension of location. More...
 

Static Protected Member Functions

static wxString GetAnchor (const wxString &location)
 Returns the anchor if present in the location. More...
 
static wxString GetLeftLocation (const wxString &location)
 Returns the left location string extracted from location. More...
 
static wxString GetProtocol (const wxString &location)
 Returns the protocol string extracted from location. More...
 
static wxString GetRightLocation (const wxString &location)
 Returns the right location string extracted from location. More...
 

Additional Inherited Members

- Protected Member Functions inherited from wxObject
void AllocExclusive ()
 Ensure that this object's data is not shared with any other object. More...
 
virtual wxObjectRefDataCreateRefData () const
 Creates a new instance of the wxObjectRefData-derived class specific to this object and returns it. More...
 
virtual wxObjectRefDataCloneRefData (const wxObjectRefData *data) const
 Creates a new instance of the wxObjectRefData-derived class specific to this object and initializes it copying data. More...
 
- Protected Attributes inherited from wxObject
wxObjectRefDatam_refData
 Pointer to an object which is the object's reference-counted data. More...
 

Constructor & Destructor Documentation

wxFileSystemHandler::wxFileSystemHandler ( )

Constructor.

Member Function Documentation

virtual bool wxFileSystemHandler::CanOpen ( const wxString location)
pure virtual

Returns true if the handler is able to open this file.

This function doesn't check whether the file exists or not, it only checks if it knows the protocol. Example:

bool MyHand::CanOpen(const wxString& location)
{
return (GetProtocol(location) == "http");
}

Must be overridden in derived handlers.

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

Works like wxFindFirstFile().

Returns the name of the first filename (within filesystem's current path) that matches wildcard. flags may be one of wxFILE (only files), wxDIR (only directories) or 0 (both).

This method is only called if CanOpen() returns true.

virtual wxString wxFileSystemHandler::FindNext ( )
virtual

Returns next filename that matches parameters passed to wxFileSystem::FindFirst.

This method is only called if CanOpen() returns true and FindFirst() returned a non-empty string.

static wxString wxFileSystemHandler::GetAnchor ( const wxString location)
staticprotected

Returns the anchor if present in the location.

See wxFSFile::GetAnchor for details.

Example:

GetAnchor("index.htm#chapter2") == "chapter2"
Note
the anchor is NOT part of the left location.
static wxString wxFileSystemHandler::GetLeftLocation ( const wxString location)
staticprotected

Returns the left location string extracted from location.

Example:

GetLeftLocation("file:myzipfile.zip#zip:index.htm") == "file:myzipfile.zip"
static wxString wxFileSystemHandler::GetMimeTypeFromExt ( const wxString location)
static

Returns the MIME type based on extension of location.

(While wxFSFile::GetMimeType() returns real MIME type - either extension-based or queried from HTTP.)

Example:

GetMimeTypeFromExt("index.htm") == "text/html"
static wxString wxFileSystemHandler::GetProtocol ( const wxString location)
staticprotected

Returns the protocol string extracted from location.

Example:

GetProtocol("file:myzipfile.zip#zip:index.htm") == "zip"
static wxString wxFileSystemHandler::GetRightLocation ( const wxString location)
staticprotected

Returns the right location string extracted from location.

Example:

GetRightLocation("file:myzipfile.zip#zip:index.htm") == "index.htm"
virtual wxFSFile* wxFileSystemHandler::OpenFile ( wxFileSystem fs,
const wxString location 
)
pure virtual

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

Must be overridden in derived handlers.

Parameters
fsParent FS (the FS from that OpenFile was called). See the ZIP handler for details of how to use it.
locationThe absolute location of file.