MemoryStream. This C# class represents a pure, in-memory stream of data. It is found in the System.IO namespace. It is derived from the Stream type.

Type uses. MemoryStream is useful when using BinaryReader and other classes that can receive streams. It can be reset—this leads to performance improvements.

Stream

Example code. First, this C# program physically reads in the bytes of specified file into the computer's memory. No more disk accesses occur after this.

byte Array

BinaryReader

using System;
using System.IO;

class Program
{
    static void Main()
    {
        // Read all bytes in from a file on the disk.
        byte[] file = File.ReadAllBytes("C:\\ICON1.png");

        // Create a memory stream from those bytes.
        using (MemoryStream memory = new MemoryStream(file))
        {
            // Use the memory stream in a binary reader.
            using (BinaryReader reader = new BinaryReader(memory))
            {
                // Read in each byte from memory.
                for (int i = 0; i < file.Length; i++)
                {
                    byte result = reader.ReadByte();
                    Console.WriteLine(result);
                }
            }
        }
    }
}
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0
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72...

A discussion. Memory is much faster than disk or network accesses. With the MemoryStream class, we can act upon the byte array stored in memory rather than a file or other resource.

A summary. MemoryStream in C# programs allows you to use in-memory byte arrays or other data as though they are streams. Instead of storing data in files, you can store data in-memory.