A directory, as we learned earlier, is a special type of a
file. Both files and directories are stored in the permanent storage device of
your computer system, abiding by the protocols as laid out by the file system
of the host Operating System. But what is a file system, anyway? A file system
is the format and rules and regulations that are set by the host Operating
System of your computer system that specifies how the files and directories in
your system are organized. The file system of MSDOS is FAT, Windows 9x is VFAT
and the same of Windows XP or Windows NT is NTFS and that of UNIX is UFS.
For working with directories in .NET, you have two classes
in the .NET Base Class Library. These classes are the Directory class and the
DirectoryInfo class and are present in the System.IO namespace. The System.IO
namespace contains a list of classes, methods and properties for accessing the
files and directories in the file system and working with them. You can use the
classes in the System.IO namespace to read and write files, list directories,
get file information, and manipulate files and directories. According to MSDN,
"The System.IO namespace contains types that allow reading and writing to
files and data streams and types that provide basic file and directory
support." The System.IO namespace contains the following classes.
·
TextReader
·
TextWriter
·
StringReader
·
StringWriter
·
BinaryReader
·
BinaryWriter
·
StreamReader
·
StreamWriter
·
File
·
FileInfo
·
Directory
·
DirectoryInfo
Let us start our discussion with the Directory class. We
will follow this up with a discussion on the DirectoryInfo class. You have a
number of static methods in the Directory class for working with directories.
All these methods are static methods and they require a security check that in
turn verifies whether the user has the necessary permission to access the file
system from within the .NET’s managed environment.
The members of the Directory class in the .NET Base Class
Library are:
·
Exists
·
CreateDirectory
·
Delete
·
Move
·
SetCreationTime
·
GetCreationTime
·
SetLastAccessTime
·
GetLastAccessTime
·
SetLastWriteTime
·
GetLastWriteTime
·
GetLogicalDrives
·
GetParent
·
GetCurrentDirectory
·
GetDirectoryRoot
·
GetDirectories
·
GetFiles
·
GetFileSystemEntries
The DirectoryInfo class is similar to the Directory class
with the exception that it contains only static methods. The methods of the
DirectoryInfo class are as follows.
·
Create
·
CreateSubDirectory
·
MoveTo
·
Delete
·
GetFiles
·
GetDirectories
·
GetFileSystemInfos
The following code snippet illustrates how you can use the
Directory class to display the list of files and directories.
Listing 1
string[] files = Directory.GetFileSystemEntries(Environment.GetFolderPath
(Environment.SpecialFolder.Personal));
string[] directories = Directory.GetDirectories (Environment.GetFolderPath
(Environment.SpecialFolder.ProgramFiles));
foreach (string file in files)
{
System.WriteLine(file);
}
foreach (string directory in directories)
{
System.WriteLine(directory);
} 
