Directories and Files
The File and Directory classes
contain
static methods and properties that encapsulate the operations
typically associated with file I/O, such as copying, moving,
deleting, renaming, and enumerating files and directories.
The actual manipulation of the contents of a file is done with a
FileStream. The File class has
methods that return a FileStream, though you may
directly instantiate a FileStream.
Reading and Writing Files
This example reads in and prints out the first line of a text file specified on the command line:
using System;
using System.IO;
class FileDumper {
static void Main(string[ ] args) {
Stream s = File.OpenRead(args[0]);
StreamReader sr = new StreamReader(s);
Console.WriteLine(sr.ReadLine( ));
sr.Close( );
}
}Examining Directories
To examine the contents
of the filesystem, use the
DirectoryInfo and FileInfo
classes, both of which are derived from a common
FileSystemInfo base class. These provide access to
most of the filesystem information, which the following example
demonstrates by replicating the results of the dir
command:
using System; using System.IO; using System.Text; class DirCommand { static void Main( ) { long numFiles=0, numDirs=0, totalBytes=0; string currentDir = Directory.GetCurrentDirectory( ); DirectoryInfo currentDirInfo = new DirectoryInfo(currentDir); StringBuilder sb = new StringBuilder( ); sb.AppendFormat(" Directory of {0}\n\n", currentDirInfo.FullName); DirectoryInfo rootDirInfo = currentDirInfo.Root; if (rootDirInfo ...