TCP で送受信

ソケット送受信クラス

System.Net.Sockets.TcpClient クラスをラップして扱いやすいように TcpCommunicator クラスを作成

public class TcpCommunicator : IDisposable
{
    public TcpCommunicator(TcpClient tcpClient)
    {
        if (tcpClient == null) throw new ArgumentNullException(nameof(tcpClient));
        this.TcpClient = tcpClient;
        this.Name = $"[{this.Socket.RemoteEndPoint}]";
    }

    public TcpCommunicator(string host, int port) : this(new TcpClient(host, port)) { }

    private TcpClient TcpClient { get; }

    protected Socket Socket => this.TcpClient?.Client;

    public string Name { get; }

    public bool IsConnecting
    {
        get
        {
            try
            {
                if ((this.TcpClient == null) || !this.TcpClient.Connected) return false;
                if (this.Socket == null) return false;
                return !(this.Socket.Poll(1, SelectMode.SelectRead) && (this.Socket.Available <= 0));
            }
            catch
            {
                return false; // 強制で切断した場合に Socket が null になるため、例外を無視
            }
        }
    }

    public void Dispose()
    {
        if (this.TcpClient != null)
        {
            this.TcpClient.Close();
            (this.TcpClient as IDisposable).Dispose();
        }
    }

    static string ToHexString(byte[] data)
    {
        if (data == null) throw new ArgumentNullException(nameof(data));
        var sb = new StringBuilder(data.Length * 2);
        foreach (var item in data) sb.Append($"{item:X2}");
        return sb.ToString();
    }

    public void Send(byte[] data)
    {
        if (data == null) throw new ArgumentNullException(nameof(data));
        if (!this.IsConnecting) throw new InvalidOperationException();
        try
        {
            Console.WriteLine($"{this.Name} << " + ToHexString(data));
            var stream = this.TcpClient.GetStream();
            stream.Write(data, 0, data.Length);
        }
        catch (Exception ex)
        {
            throw new ApplicationException("Attempt to send failed.", ex);
        }
    }

    public byte[] Receive()
    {
        if (!this.IsConnecting) throw new InvalidOperationException();
        try
        {
            using (var memory = new MemoryStream())
            {
                var stream = this.TcpClient.GetStream();
                while (stream.DataAvailable)
                {
                    var buffer = new byte[8192];
                    var count = stream.Read(buffer, 0, buffer.Length);
                    if (count > 0)
                    {
                        var data = new byte[count];
                        Array.Copy(buffer, 0, data, 0, count);
                        Console.WriteLine($"{this.Name} >> " + ToHexString(data));
                        memory.Write(data, 0, data.Length);
                    }
                }
                return memory.ToArray();
            }
        }
        catch (Exception ex)
        {
            throw new ApplicationException("Attempt to receive failed.", ex);
        }
    }
}