Stream Me Up, Scotty (part 2) - The Application (
Page 6 of 6 )
Now that you know the
various techniques, it's time to build a simple file manager. You can download
the
complete source code from here - I'll just give
you a quick tour through the various sections.
"index.php" sets up the
main interface for the applications. On the left side is a list of available
functions, while the right side contains a listing of files and directories.
Directories can be entered by clicking on them, while files located within the
Web server document root can be downloaded by clicking on them (files outside
the server root cannot be downloaded). The script "index.php" can accept the
parameter $dir, which indicates the directory to be displayed.
All this
takes place via two functions, links() and filelist(), which you can see in the
file "links.php" - the former sets up the links on the left side, while the
latter uses the opendir() and other file information functions to obtain
information on the size and permissions of files in the directory. Directories
are set up as active hyperlinks - once a directory is clicked, the script
"index.php" is called once again, but with a different $dir value.
At any
point, you can access the functions on the left side - "upload.php" accepts a
file for upload, "mkdir.php" allows you to create a new directory in the current
locations, "rmdir.php" reverses the process, and "rmfile.php" allows you to
delete one or more files. All these scripts accept a single parameter, $dir,
which tells them where their respective actions are to be performed.
It's
also possible to download files by turning them into clickable hyperlinks - the
application checks to first make sure that the files are in the Web server
DocumentRoot, sets a flag if they are, and then turns each file into a
hyperlink. Again, there are security implications here - so be
careful!
And once you're done, it might be worthwhile to go back to the
equivalent file browser we built in the first part of this article. If you
compare the two approaches, other things being equal, you'll notice that the
HTTP file browser is much faster than the FTP file browser, and also allows more
flexibility when manipulating files.
Hopefully, this exercise has helped
you gain a clearer idea of PHP's file manipulation capabilities, together with
an understanding of what is and what isn't possible. I'm off - but I'll see you
soon!
This
article copyright Melonfire 2000. All
rights reserved.
