docs/latex/wx/filesysh.tex

   1 %
   2 % automatically generated by HelpGen from
   3 % filesystemhandler.tex at 21/Mar/99 23:00:52
   4 %
   5
   6 \section{\class{wxFileSystemHandler}}\label{wxfilesystemhandler}
   7
   8 Classes derived from wxFileSystemHandler are used
   9 to access virtual file systems. Its public interface consists
  10 of two methods: \helpref{CanOpen}{wxfilesystemhandlercanopen}
  11 and \helpref{OpenFile}{wxfilesystemhandleropenfile}.
  12 It provides additional protected methods to simplify the process
  13 of opening the file: GetProtocol, GetLeftLocation, GetRightLocation,
  14 GetAnchor, GetMimeTypeFromExt.
  15
  16 Please have a look at \helpref{overview}{fs} if you don't know how locations
  17 are constructed.
  18
  19 Also consult \helpref{list of available handlers}{fs}.
  20
  21 \perlnote{In wxPerl, you need to derive your file system handler class
  22 from Wx::PlFileSystemHandler.}
  23
  24 \wxheading{Notes}
  25
  26 \begin{itemize}\itemsep=0pt
  27 \item The handlers are shared by all instances of wxFileSystem.
  28 \item wxHTML library provides handlers for local files and HTTP or FTP protocol
  29 \item The {\it location} parameter passed to OpenFile or CanOpen methods
  30 is always an {\bf absolute} path. You don't need to check the FS's current path.
  31 \end{itemize}
  32
  33 \wxheading{Derived from}
  34
  35 \helpref{wxObject}{wxobject}
  36
  37 \wxheading{Include files}
  38
  39 <wx/filesys.h>
  40
  41 \wxheading{Library}
  42
  43 \helpref{wxBase}{librarieslist}
  44
  45 \wxheading{See also}
  46
  47 \helpref{wxFileSystem}{wxfilesystem},
  48 \helpref{wxFSFile}{wxfsfile},
  49 \helpref{Overview}{fs}
  50
  51 \latexignore{\rtfignore{\wxheading{Members}}}
  52
  53
  54 \membersection{wxFileSystemHandler::wxFileSystemHandler}\label{wxfilesystemhandlerwxfilesystemhandler}
  55
  56 \func{}{wxFileSystemHandler}{\void}
  57
  58 Constructor.
  59
  60 \membersection{wxFileSystemHandler::CanOpen}\label{wxfilesystemhandlercanopen}
  61
  62 \func{virtual bool}{CanOpen}{\param{const wxString\& }{location}}
  63
  64 Returns true if the handler is able to open this file. This function doesn't
  65 check whether the file exists or not, it only checks if it knows the protocol.
  66 Example:
  67
  68 \begin{verbatim}
  69 bool MyHand::CanOpen(const wxString& location)
  70 {
  71     return (GetProtocol(location) == "http");
  72 }
  73 \end{verbatim}
  74
  75 Must be overridden in derived handlers.
  76
  77 \membersection{wxFileSystemHandler::GetAnchor}\label{wxfilesystemhandlergetanchor}
  78
  79 \constfunc{wxString}{GetAnchor}{\param{const wxString\& }{location}}
  80
  81 Returns the anchor if present in the location.
  82 See \helpref{wxFSFile}{wxfsfilegetanchor} for details.
  83
  84 Example: GetAnchor("index.htm\#chapter2") == "chapter2"
  85
  86 {\bf Note:} the anchor is NOT part of the left location.
  87
  88 \membersection{wxFileSystemHandler::GetLeftLocation}\label{wxfilesystemhandlergetleftlocation}
  89
  90 \constfunc{wxString}{GetLeftLocation}{\param{const wxString\& }{location}}
  91
  92 Returns the left location string extracted from {\it location}.
  93
  94 Example: GetLeftLocation("file:myzipfile.zip\#zip:index.htm") == "file:myzipfile.zip"
  95
  96 \membersection{wxFileSystemHandler::GetMimeTypeFromExt}\label{wxfilesystemhandlergetmimetypefromext}
  97
  98 \func{wxString}{GetMimeTypeFromExt}{\param{const wxString\& }{location}}
  99
 100 Returns the MIME type based on {\bf extension} of {\it location}. (While wxFSFile::GetMimeType
 101 returns real MIME type - either extension-based or queried from HTTP.)
 102
 103 Example : GetMimeTypeFromExt("index.htm") == "text/html"
 104
 105 \membersection{wxFileSystemHandler::GetProtocol}\label{wxfilesystemhandlergetprotocol}
 106
 107 \constfunc{wxString}{GetProtocol}{\param{const wxString\& }{location}}
 108
 109 Returns the protocol string extracted from {\it location}.
 110
 111 Example: GetProtocol("file:myzipfile.zip\#zip:index.htm") == "zip"
 112
 113 \membersection{wxFileSystemHandler::GetRightLocation}\label{wxfilesystemhandlergetrightlocation}
 114
 115 \constfunc{wxString}{GetRightLocation}{\param{const wxString\& }{location}}
 116
 117 Returns the right location string extracted from {\it location}.
 118
 119 Example : GetRightLocation("file:myzipfile.zip\#zip:index.htm") == "index.htm"
 120
 121 \membersection{wxFileSystemHandler::FindFirst}\label{wxfilesystemhandlerfindfirst}
 122
 123 \func{virtual wxString}{FindFirst}{\param{const wxString\& }{wildcard}, \param{int }{flags = 0}}
 124
 125 Works like \helpref{wxFindFirstFile}{wxfindfirstfile}. Returns name of the first
 126 filename (within filesystem's current path) that matches {\it wildcard}. {\it flags} may be one of
 127 wxFILE (only files), wxDIR (only directories) or 0 (both).
 128
 129 This method is only called if \helpref{CanOpen}{wxfilesystemhandlercanopen} returns true.
 130
 131 \membersection{wxFileSystemHandler::FindNext}\label{wxfilesystemhandlerfindnext}
 132
 133 \func{virtual wxString}{FindNext}{\void}
 134
 135 Returns next filename that matches parameters passed to \helpref{FindFirst}{wxfilesystemfindfirst}.
 136
 137 This method is only called if \helpref{CanOpen}{wxfilesystemhandlercanopen} returns true and FindFirst
 138 returned a non-empty string.
 139
 140 \membersection{wxFileSystemHandler::OpenFile}\label{wxfilesystemhandleropenfile}
 141
 142 \func{virtual wxFSFile*}{OpenFile}{\param{wxFileSystem\& }{fs}, \param{const wxString\& }{location}}
 143
 144 Opens the file and returns wxFSFile pointer or NULL if failed.
 145
 146 Must be overridden in derived handlers.
 147
 148 \wxheading{Parameters}
 149
 150 \docparam{fs}{Parent FS (the FS from that OpenFile was called). See ZIP handler
 151 for details of how to use it.}
 152
 153 \docparam{location}{The {\bf absolute} location of file.}
 154