Question

Let’s say I have two classes that look like this:

public class ByteFilter
{
    private Func <int, byte[]> readBytes;
    private Action<byte[]> writeBytes;

    public ByteFilter(Func <int, byte[]> readBytes, Action<byte[]> writeBytes)
    {
        this.readBytes = readBytes;
        this.writeBytes = writeBytes;
    }
}

public class PacketFilter
{
    private Func<Packet> readPacket;
    private Action<Packet> writePacket;

    Public PacketFilter(Func<Packet> readPacket, Action<Packet> writePacket)
    {
        this.readBytes = readPacket;
        this.writeBytes = writePacket;
    }
}

Either class may be instantiated at runtime (via Activator.CreateInstance) to perform a filtering function. The read and write methods will be hooked up at runtime to methods from other classes that will provide and accept byte arrays or packets.

Within each filter is additional code that performs the filtering function:

public void Process()
{
    while (!done)
    {
        byte[] data = ReadBytes();      // or ReadPacket()
        // perform filtering on data
        WriteBytes(data);               // or WritePacket()
    }
}

If only one of the above constructor signatures will be present in each filter, how do I determine (using Reflection) which constructor signature is present, so that I can hook up the appropriate methods at runtime?

Note: If I’m daffy and doing this the wrong way, I’d like to know that too.

Answer 1

Can’t you do something like?

bool packetConstructor = 
            typeof(PacketFilter).GetConstructors()
                                .Any(c => c.GetParameters()
                                           .Any(p => p.ParameterType 
                                                    == typeof(Func<Packet>)));

replacing typeof(PacketFilter) with appropriate instance.