C# Structures

Structure in C#

• A value type that stores a collection of variables of different data types under a single unit
• Similar to a class, being a user-defined data type that holds multiple data types
• Allows users to define their own data types, also known as User-Defined Data Types
• Although a value type, structures can be modified according to requirements

File Handling in C#

• File handling refers to the process of storing and retrieving data from files using a program.
• In C#, file handling allows storing data in a file and fetching/extracting it to work again in any program.

File Operations

• File handling involves various operations like creating, reading, writing, and appending files.
• Reading and writing are the two basic operations used in file handling.
• A file becomes a stream when opened for writing and reading.

Streams

• A stream is a sequence of bytes used for communication.
• Two streams can be formed from a file: input stream for reading and output stream for writing.
• The System.IO namespace in C# contains classes that handle input and output streams and provide information about file and directory structures.

C# Stream Classes

• System.IO.Stream is an abstract class that provides standard methods to transfer bytes to a source.
• FileStream reads or writes bytes from/to a physical file.
• MemoryStream reads or writes bytes stored in memory.
• BufferedStream improves I/O operations' performance.
• NetworkStream reads or writes bytes from a network socket.
• PipeStream reads or writes bytes from different processes.
• CryptoStream links data streams to cryptographic transformations.

StreamReader and StreamWriter

• StreamReader is a helper class that reads characters from a Stream by converting bytes into characters.
• StreamWriter is a helper class that writes a string to a Stream by converting characters into bytes.

File System

• A file system refers to the structure, rules, and regulations defined by the host Operating System.
• A directory is a special type of file that can store other files and directories.
• The System.IO namespace contains types that enable reading and writing to files and data streams, as well as support for basic file and directory operations.

Directory Class

• The Directory class contains static methods for creating, copying, moving, and deleting directories.