System.IO Namespace

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

The System.IO namespace contains enumerations for file modes, file access, file sharing, and classes for path operations and manipulating streams. Windows Phone applications do not use the file system of the operating system and are restricted to using isolated storage to persist and access files, so this namespace does not provide any additional functionality. For more information about how Windows Phone applications use isolated storage, see Data for Windows Phone 8.

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.
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 Infrastructure. The exception that is thrown when part of a file or directory cannot be found.
EndOfStreamException The exception that is thrown when reading is attempted past the end of a stream.
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 fails.
FileStream Exposes a Stream around a file, supporting both synchronous and asynchronous read and write operations.
FileSystemInfo Provides the base class for both FileInfo and DirectoryInfo objects.
InvalidDataException The exception that is thrown when a data stream is in an invalid format.
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.
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 Infrastructure. Provides access to unmanaged blocks of memory from managed code.
WindowsRuntimeStorageExtensions
WindowsRuntimeStreamExtensions

Enumerations

Enumeration Description
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.
FileShare Contains constants for controlling the kind of access other IsolatedStorageFileStream objects can have to the same file.
SeekOrigin Provides the fields that represent reference points in streams for seeking.