How to use a common interface between SerialPort and NetworkStream in C#?

Question

I have a C# method _TryReadChunk that reads bytes from a SerialPort connection:

private bool _TryReadChunk(SerialPort connection, int n_exp, out byte[] received)
{
    ...
    received = new byte[n_exp];
    int bytes_read = connection.Read(received, length, n_exp);
    ...
}

I need the same method again, but reading from a NetworkStream. I thought that an elegant way to do this would be to use a generic method like

private bool _TryReadChunk<T> (T connection, int n_exp, out byte[] received)
{
    ...
}

However, I somehow need to add a constraint to the method that T has to implement a Read method. First I thought to define an interface like

interface _CanRead 
{
    int Read(byte[] buffer, int offset, int count);
}

and require

private bool _TryReadChunk<T> (T connection, int n_exp, out byte[] received) where T : _CanRead
{
    ...
}

but when reading more I got the impression that SerialPort and NetworkStream would have to implement that interface explicitly, which, of course, they don't.

I am new to generics and feel a bit stuck. Is there a way to do what I want or should I just bite the bullet and implement my method twice?

Answer 1

This probably isn't a good application for generics, but it is for using base classes. SerialPort has a property called BaseStream, which is a Stream. NetworkStream also derives from stream, so you could do something like this:

private bool _TryReadChunk(Stream connection, int n_exp, out byte[] received)
{
    ...
}

Then pass in the SerialPort.BaseStream object or the NetworkStream object, you can then use the standard Stream.Read methods to read the data out the same way.

Answer 2

You don't have to re implement which is already available. You can use the SerialPort.BaseStream property and use it directly.

NetworkStream is already a Stream and SerialPort.BaseStream exposes a Stream . You can take Stream as a parameter to your TryReadChunk method and read the stream directly.