Page 359 - Beginning PHP 5.3

Chapter 11: Working with Files and Directories
< p > < ?php echo $dirPath ? > contains the following files and folders: < /p >

< ul >
< ?php

while ( $file = $dir- > read() ) {

if ( $file != “.” & & $file != “..” ) echo “ < li > $file < /li > ”;
}

$dir- > close();

? >
< /ul >
< /body >
< /html >

Telling a File from a Directory
Often you need to know whether a particular file is a regular file or a directory. For example, suppose
you want to write some code that travels down through a tree of folders. You ’ d need to detect when a
file was actually a folder, so you could enter the folder and continue working through the tree. By the
same token, if you want to display the files in a folder, you ’ d need to detect when a file is in fact a
regular file.

Remember: both directories and regular files are all essentially files, but directories are a special kind
of file.

PHP has two functions to help you test for a file or a directory:
❑ is_dir() — Returns true if the given filename refers to a directory
❑ is_file() — Returns true if the given filename refers to a regular file

Here ’ s a simple example that determines if a file called myfile is a file or a directory:
$filename = “myfile”;

if ( is_dir( $filename ) ) {
echo “$filename is a directory.”;
} elseif ( is_file( $filename ) ) {
echo “$filename is a file.”;
} else {
echo “$filename is neither a directory nor a file.”;

}

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