Asynchronously reads a byte array from the NetworkStream object.

NetworkStreamHelper.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Sockets;
using System.Threading.Tasks;

public static class NetworkStreamHelper
{
    /// <summary>
    /// Asynchronously reads a byte array from the NetworkStream object.
    /// </summary>
    /// <param name="stream">The NetworkStream object to read.</param>
    /// <param name="count">The byte array size to read.</param>
    /// <param name="dataChunkSize">The data chunk size that used for reading chunks from the stream.</param>
    /// <returns>Returns a task presents the asynchronious array read operation.</returns>
    public static async Task<Byte[]> ReadBytesAsync(this NetworkStream stream, Int32 count, Int32 dataChunkSize = 512)
    {
        if (count <= 0)
        {
            throw new ArgumentException("count should not be less 1");
        }
        if (dataChunkSize <= 0)
        {
            throw new ArgumentException("dataChunkSize should not be less 1");
        }

        var dataChunk = new Byte[dataChunkSize];
        var destination = new List<Byte>(count);
        var currentBytesRead = 0;
        var remainedBytesToRead = count;
        var bytesToRead = 0;
        var done = false;

        while (!done)
        {
            bytesToRead = remainedBytesToRead > dataChunk.Length ? dataChunk.Length : remainedBytesToRead;
            currentBytesRead = await stream.ReadAsync(dataChunk, 0, bytesToRead);
            destination.AddRange(dataChunk.Take(currentBytesRead));
            remainedBytesToRead -= currentBytesRead;
            done = remainedBytesToRead == 0;
        }

        return destination.ToArray();
    }
}