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.

 Classes

	Class	Description
	BinaryReader	Reads primitive data types as binary values in a specific encoding.
	BinaryWriter	Writes primitive types in binary to a stream and supports writing strings in a specific encoding.
	BufferedStream	Adds a buffering layer to read and write operations on another stream. This class cannot be inherited.
	Directory	Exposes static methods for creating, moving, and enumerating through directories and subdirectories. This class cannot be inherited.
	DirectoryInfo	Exposes instance methods for creating, moving, and enumerating through directories and subdirectories. This class cannot be inherited.
	DirectoryNotFoundException	The exception that is thrown when part of a file or directory cannot be found.
	DriveInfo	Provides access to information on a drive.
	DriveNotFoundException	The exception that is thrown when trying to access a drive or share that is not available.
	EndOfStreamException	The exception that is thrown when reading is attempted past the end of a stream.
	ErrorEventArgs	Provides data for the Error event.
	File	Provides static methods for the creation, copying, deletion, moving, and opening of files, and aids in the creation of FileStream objects.
	FileInfo	Provides instance methods for the creation, copying, deletion, moving, and opening of files, and aids in the creation of FileStream objects. This class cannot be inherited.
	FileLoadException	The exception that is thrown when a managed assembly is found but cannot be loaded.
	FileNotFoundException	The exception that is thrown when an attempt to access a file that does not exist on disk fails.
	FileStream	Exposes a Stream around a file, supporting both synchronous and asynchronous read and write operations.
	FileSystemEventArgs	Provides data for the directory events: Changed, Created, Deleted.
	FileSystemInfo	Provides the base class for both FileInfo and DirectoryInfo objects.
	FileSystemWatcher	Listens to the file system change notifications and raises events when a directory, or file in a directory, changes.
	InternalBufferOverflowException	The exception thrown when the internal buffer overflows.
	InvalidDataException	The exception that is thrown when a data stream is in an invalid format.
	IODescriptionAttribute	Sets the description visual designers can display when referencing an event, extender, or property.
	IOException	The exception that is thrown when an I/O error occurs.
	MemoryStream	Creates a stream whose backing store is memory.
	Path	Performs operations on String instances that contain file or directory path information. These operations are performed in a cross-platform manner.
	PathTooLongException	The exception that is thrown when a pathname or filename is longer than the system-defined maximum length.
	RenamedEventArgs	Provides data for the Renamed event.
	Stream	Provides a generic view of a sequence of bytes.
	StreamReader	Implements a TextReader that reads characters from a byte stream in a particular encoding.
	StreamWriter	Implements a TextWriter for writing characters to a stream in a particular encoding.
	StringReader	Implements a TextReader that reads from a string.
	StringWriter	Implements a TextWriter for writing information to a string. The information is stored in an underlying StringBuilder.
	TextReader	Represents a reader that can read a sequential series of characters.
	TextWriter	Represents a writer that can write a sequential series of characters. This class is abstract.
	UnmanagedMemoryStream	Provides access to unmanaged blocks of memory from managed code.

 Structures

	Structure	Description
	WaitForChangedResult	Contains information on the change that occurred.

 Delegates

	Delegate	Description
	ErrorEventHandler	Represents the method that will handle the Error event of a FileSystemWatcher object.
	FileSystemEventHandler	Represents the method that will handle the Changed, Created, or Deleted event of a FileSystemWatcher class.
	RenamedEventHandler	Represents the method that will handle the Renamed event of a FileSystemWatcher class.

 Enumerations

	Enumeration	Description
	DriveType	Defines constants for drive types, including CDRom, Fixed, Network, NoRootDirectory, Ram, Removable, and Unknown.
	FileAccess	Defines constants for read, write, or read/write access to a file.
	FileAttributes	Provides attributes for files and directories.
	FileMode	Specifies how the operating system should open a file.
	FileOptions	Represents additional options for creating a FileStream object.
	FileShare	Contains constants for controlling the kind of access other FileStream objects can have to the same file.
	NotifyFilters	Specifies changes to watch for in a file or folder.
	SearchOption	Specifies whether to search the current directory, or the current directory and all subdirectories.
	SeekOrigin	Provides the fields that represent reference points in streams for seeking.
	WatcherChangeTypes	Changes that might occur to a file or directory.