Similar to the Directory and the DirectoryInfo class that we
use when working with Directories, you have the File and the FileInfo classes
for working with files in C#. The File class contains a number of static
methods that can be used for creating, opening, copying, deleting, and moving
of files in your file system. The members of the File class are as follows.
·
Copy
·
Exists
·
Open
·
Delete
·
Move
·
Create
·
CreateText
·
AppendText
·
GetCreationTime
·
GetLastAccessTime
·
GetLastWriteTime
The following code snippet illustrates how you can use the
File class to check whether a file exists and if so, it sets the creation time,
last access time and the last write time of the file. It then deletes the file
using the Delete() method of the File class.
Listing 2
if (File.Exists(@"C:\Test.txt"))
{
File.SetCreationTime(@"C:\Test.txt", Date.Now);
File.SetLastAccessTime(@"C:\Test.txt", Date.Now);
File.SetLastWriteTime(@"C:\Test.txt", Date.Now);
}
if (File.Exists(@"C:\Test.txt"))
File.Delete(@"C:\Test.txt");Please note that I have provided you some of the most
important members of the classes Directory, DirectoryInfo, File and FileInfo.
You can refer to MSDN for a complete list of the members of each of these
classes.
Unlike the File class, the FileInfo class contains not only
static methods, but the FileInfo class also contains instance methods to
perform various file operations in your file system. Note that the FileInfo
class is abstract in nature. The following is the list of members of the
FileInfo class.
·
Open
·
Create
·
Delete
·
CopyTo
·
MoveTo
·
CreateText
·
AppendText
Further to this, you have some enumerators that contain
fields that correspond to the file modes, file share and the file access
permissions, etc. The following is the complete list of the enumerators in the
System.IO namespace.
·
DriveType
·
FileAccess
·
FileAttributes
·
FileMode
·
FileOption
·
FileShare
·
NotifyFilters
·
SearchOption
·
SeekOrigin
·
WatcherChangeTypes
I will discuss only the FileMode, FileShare, and FileAccess
enumerators here. You can refer to the MSDN for information on the other
enumerators.
The available file modes that are contained in the FileMode
enumerator are the following.
·
Open
·
Truncate
·
Create
·
CreateNew
·
Append
The truncate file mode is used to indicate that an existing
file should be opened and the contents of the file should be truncated so that
its size becomes bytes. I will skip a discussion on the other file modes as
their names are self explanatory and should be well understood by the reader.
The FileShare enumerator is used to specify the level of access for a file in
the file system that is currently in use. The FileShare enumerator,
"Contains constants for controlling the kind of access other FileStream
objects can have to the same file." The available fields in the FileShare
enumerator are listed here.
·
None
·
Read
·
ReadWrite
·
Delete
·
Write
The FileAccess enumerator contains fields that correspond to
read, write and read/write access to a file in the file system. The following
are the fields in the FileAccess enumerator.
·
Read
·
Write
·
ReadWrite
