Page 369 - Beginning PHP 5.3

Chapter 11: Working with Files and Directories
echo ‘ < td > ’ . filesize( $filepath ) . ‘ < /td > ’;
/
echo ‘ < td > ’ . date( “M j, Y H:i:s”, filemtime( $filepath ) ) . ‘ < /td > <

tr > ’;
}

}
To display each file in the table, the script wraps a link around the filename to allow the user to edit the
file. The link ’ s URL includes the query string ” ?filename= ” followed by the name of the file to edit.
Notice that the filename is encoded in the query string by passing it through the urlencode()
function. The script also displays the file ’ s size by calling the filesize() function. Finally, the file ’ s
“ last modified ” time is displayed by calling the filemtime() function and passing the resulting
timestamp to the date() function to format it.
Find out more about urlencode() in Chapter 10, and date() in Chapter 16.

Once the loop ’ s finished, the function closes the directory and displays the form for creating a new file.
The form includes a filename text field and a createFile submit button.

The displayEditForm() Function

When the user clicks a file to edit, the displayEditForm() function is called to display the file contents
for editing. This function can take an optional $filename argument containing the filename of the file
to edit; if this isn ’ t passed, it looks up the filename in the query string, passing it through basename() to
ensure that no additional path information is in the filename; this is a good security measure, because it
thwarts any attempt to edit files outside the designated folder. Furthermore, if the filename is empty for
some reason, the script exits with an error:

function displayEditForm( $filename=”” ) {
if ( !$filename ) $filename = basename( $_GET[“filename”] );
if ( !$filename ) die( “Invalid filename” );
Next the function stores the full path to the file in a $filepath variable (because this path is needed
many times in the function), and checks to make sure the file to edit actually exists — if it doesn ’ t, it exits
with a “ File not found ” message:

$filepath = PATH_TO_FILES . “/$filename”;
if ( !file_exists( $filepath ) ) die( “File not found” );

The rest of the function calls displayPageHeader() to output the standard page header markup, then
displays the name of the file being edited, as well as the HTML form for editing the file. The form
consists of a hidden field storing the filename of the file being edited; a text area for the file contents; and
Save File and Cancel buttons. The file ’ s contents are displayed in the text area simply by calling file_
get_contents() and outputting the result.

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