System.IO.Stream Class

The System.IO.Stream abstract class provides a generic view of a sequence of bytes, supporting reading, writing, and seeking operations.

Overview

Properties

Methods

Examples

Namespace

System.IO

Assembly

System.Runtime.dll

Base Class

object

Derived Types

Properties

Name	Type	Description
`CanRead`	bool	Indicates whether the current stream supports reading.
`CanSeek`	bool	Indicates whether the current stream supports seeking.
`CanWrite`	bool	Indicates whether the current stream supports writing.
`Length`	long	Gets the length in bytes of the stream.
`Position`	long	Gets or sets the current position within the stream.

Methods

Name	Signature	Description
`Read`	`int Read(byte[] buffer, int offset, int count)`	Reads a block of bytes from the stream and writes the data to a buffer.
`Write`	`void Write(byte[] buffer, int offset, int count)`	Writes a block of bytes to the stream from a buffer.
`Seek`	`long Seek(long offset, SeekOrigin origin)`	Sets the position within the current stream.
`Flush`	`void Flush()`	Clears all buffers for the current writer and causes any buffered data to be written to the underlying device.
`CopyToAsync`	`Task CopyToAsync(Stream destination, int bufferSize = 81920, CancellationToken cancellationToken = default)`	Asynchronously reads the bytes from the current stream and writes them to another stream.
`Dispose`	`void Dispose()`	Releases the unmanaged resources used by the Stream and optionally releases the managed resources.

Example: Copying a file using Stream

using System;
using System.IO;

class Program
{
    static void Main()
    {
        using var source = new FileStream("source.bin", FileMode.Open, FileAccess.Read);
        using var destination = new FileStream("dest.bin", FileMode.Create, FileAccess.Write);
        source.CopyTo(destination);
        Console.WriteLine("Copy completed.");
    }
}

For more advanced scenarios see the Asynchronous Streaming guide.