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{See also}
  42
  43 \helpref{wxFileSystem}{wxfilesystem},
  44 \helpref{wxFSFile}{wxfsfile},
  45 \helpref{Overview}{fs}
  46
  47 \latexignore{\rtfignore{\wxheading{Members}}}
  48
  49
  50 \membersection{wxFileSystemHandler::wxFileSystemHandler}\label{wxfilesystemhandlerwxfilesystemhandler}
  51
  52 \func{}{wxFileSystemHandler}{\void}
  53
  54 Constructor.
  55
  56 \membersection{wxFileSystemHandler::CanOpen}\label{wxfilesystemhandlercanopen}
  57
  58 \func{virtual bool}{CanOpen}{\param{const wxString\& }{location}}
  59
  60 Returns true if the handler is able to open this file. This function doesn't
  61 check whether the file exists or not, it only checks if it knows the protocol.
  62 Example:
  63
  64 \begin{verbatim}
  65 bool MyHand::CanOpen(const wxString& location)
  66 {
  67     return (GetProtocol(location) == "http");
  68 }
  69 \end{verbatim}
  70
  71 Must be overridden in derived handlers.
  72
  73 \membersection{wxFileSystemHandler::GetAnchor}\label{wxfilesystemhandlergetanchor}
  74
  75 \constfunc{wxString}{GetAnchor}{\param{const wxString\& }{location}}
  76
  77 Returns the anchor if present in the location.
  78 See \helpref{wxFSFile}{wxfsfilegetanchor} for details.
  79
  80 Example: GetAnchor("index.htm\#chapter2") == "chapter2"
  81
  82 {\bf Note:} the anchor is NOT part of the left location.
  83
  84 \membersection{wxFileSystemHandler::GetLeftLocation}\label{wxfilesystemhandlergetleftlocation}
  85
  86 \constfunc{wxString}{GetLeftLocation}{\param{const wxString\& }{location}}
  87
  88 Returns the left location string extracted from {\it location}.
  89
  90 Example: GetLeftLocation("file:myzipfile.zip\#zip:index.htm") == "file:myzipfile.zip"
  91
  92 \membersection{wxFileSystemHandler::GetMimeTypeFromExt}\label{wxfilesystemhandlergetmimetypefromext}
  93
  94 \func{wxString}{GetMimeTypeFromExt}{\param{const wxString\& }{location}}
  95
  96 Returns the MIME type based on {\bf extension} of {\it location}. (While wxFSFile::GetMimeType
  97 returns real MIME type - either extension-based or queried from HTTP.)
  98
  99 Example : GetMimeTypeFromExt("index.htm") == "text/html"
 100
 101 \membersection{wxFileSystemHandler::GetProtocol}\label{wxfilesystemhandlergetprotocol}
 102
 103 \constfunc{wxString}{GetProtocol}{\param{const wxString\& }{location}}
 104
 105 Returns the protocol string extracted from {\it location}.
 106
 107 Example: GetProtocol("file:myzipfile.zip\#zip:index.htm") == "zip"
 108
 109 \membersection{wxFileSystemHandler::GetRightLocation}\label{wxfilesystemhandlergetrightlocation}
 110
 111 \constfunc{wxString}{GetRightLocation}{\param{const wxString\& }{location}}
 112
 113 Returns the right location string extracted from {\it location}.
 114
 115 Example : GetRightLocation("file:myzipfile.zip\#zip:index.htm") == "index.htm"
 116
 117 \membersection{wxFileSystemHandler::FindFirst}\label{wxfilesystemhandlerfindfirst}
 118
 119 \func{virtual wxString}{FindFirst}{\param{const wxString\& }{wildcard}, \param{int }{flags = 0}}
 120
 121 Works like \helpref{wxFindFirstFile}{wxfindfirstfile}. Returns name of the first
 122 filename (within filesystem's current path) that matches {\it wildcard}. {\it flags} may be one of
 123 wxFILE (only files), wxDIR (only directories) or 0 (both).
 124
 125 This method is only called if \helpref{CanOpen}{wxfilesystemhandlercanopen} returns true.
 126
 127 \membersection{wxFileSystemHandler::FindNext}\label{wxfilesystemhandlerfindnext}
 128
 129 \func{virtual wxString}{FindNext}{\void}
 130
 131 Returns next filename that matches parameters passed to \helpref{FindFirst}{wxfilesystemfindfirst}.
 132
 133 This method is only called if \helpref{CanOpen}{wxfilesystemhandlercanopen} returns true and FindFirst
 134 returned a non-empty string.
 135
 136 \membersection{wxFileSystemHandler::OpenFile}\label{wxfilesystemhandleropenfile}
 137
 138 \func{virtual wxFSFile*}{OpenFile}{\param{wxFileSystem\& }{fs}, \param{const wxString\& }{location}}
 139
 140 Opens the file and returns wxFSFile pointer or NULL if failed.
 141
 142 Must be overridden in derived handlers.
 143
 144 \wxheading{Parameters}
 145
 146 \docparam{fs}{Parent FS (the FS from that OpenFile was called). See ZIP handler
 147 for details of how to use it.}
 148
 149 \docparam{location}{The {\bf absolute} location of file.}
 150