parameter less constructor error

Question

I'm trying to make my client subscribe to events that happen on my server.

I have an interface that looks like this:

public delegate void RemoteEventHandler(object sender, ClientEventArgs args);


[Serializable]
public class ClientEventArgs : EventArgs
{
    public ClientEventArgs()
    { }

    public ClientEventArgs(Client _client)
    {
        MyClient = _client;
    }
    public Client MyClient { get; set; }
}

public interface IMonitor
{
    event RemoteEventHandler RemoteEvent;
}

My Server Class looks like this:

public class ConnectionManager : MarshalByRefObject, IMonitor
{
    public event RemoteEventHandler RemoteEvent;

    // call the below code when th event should fire.
     if (RemoteEvent != null)
            RemoteEvent(this, new ClientEventArgs(e.MyClient));
}

Then To set my channels up on the server I do this:

BinaryServerFormatterSinkProvider provider = new BinaryServerFormatterSinkProvider();
provider.TypeFilterLevel = TypeFilterLevel.Full;
IDictionary props = new Hashtable();
props["port"] = 5001;
TcpChannel channel = new TcpChannel(props, null, provider);
ChannelServices.RegisterChannel(channel, false);
RemotingConfiguration.RegisterWellKnownServiceType(
typeof(ConnectionManager),
ConnectionManager",
WellKnownObjectMode.Singleton);

And On the client to set the channels up and subscribe to the event:

TcpChannel channel = new TcpChannel();
        ChannelServices.RegisterChannel(channel, false);
        _monitorObject = (IMonitor)Activator.GetObject(
            typeof(IMonitor),
            "tcp://localhost:5001/ConnectionManager");

_monitorObject.RemoteEvent += _monitorObject_RemoteEvent;

Can anyone explain where this is going wrong please?

Exception:

System.MissingMethodException was unhandled HResult=-2146233069 Message=No parameterless constructor defined for this object.
Source=mscorlib

It's failing to load the main assembly or one of its dependencies? — , Apr 17 '14 at 14:10
Then you probably are missing a referenced assembly. Did you only copy the exe? — Patrick Hofman, Apr 17 '14 at 14:11
After fixing the reference, im getting a no parameter less constructor error? — , Apr 17 '14 at 14:18
You provided a nice stack trace, but not the actual exception... — Ben Voigt, Apr 17 '14 at 14:40
@BenVoigt The stack trace has been replaced by the exception. — , Apr 17 '14 at 14:47

score 0 · Accepted Answer · answered Apr 17 '14 at 14:24

0

To answer your last question: when using Serializable you need a constructor without parameters. So this one would definitely fail:

[Serializable]
public class ClientEventArgs : EventArgs
{
    public ClientEventArgs(Client _client)
    {
        MyClient = _client;
    }
    public Client MyClient { get; set; }
}

You need to add a parameterless constructor:

[Serializable]
public class ClientEventArgs : EventArgs
{
    public ClientEventArgs()
    { }

    public ClientEventArgs(Client _client)
    {
        MyClient = _client;
    }
    public Client MyClient { get; set; }
}

answered Apr 17 '14 at 14:24

Patrick Hofman

153,850
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thanks for your response, after rebuilding its still throwing the same error though. – Apr 17 '14 at 14:28
Are you sure there are no other places with this problem? Maybe the Exception will tell the failing class? – Patrick Hofman Apr 17 '14 at 14:29
The only reference to [Serializable] is in the class from above. Thanks for your patience ! – Apr 17 '14 at 14:31
And what about your `Client` class. It is referenced in the `EventArgs`. – Patrick Hofman Apr 17 '14 at 14:34
I've changed that object to type string, do I need to add anything else if ive done that? – Apr 17 '14 at 14:35
Not as far as I can see. Give it a try. – Patrick Hofman Apr 17 '14 at 14:36
let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/50890/discussion-between-lewis-and-patrick-hofman) – Apr 17 '14 at 14:39

score 0 · Answer 2 · answered Apr 17 '14 at 14:53

0

My money is on your ConnectionManager class not having a default / parameterless constructor. The remoting infrastructure needs to be able to create an instance of it on the server end.

answered Apr 17 '14 at 14:53

x0n

51,312
7
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Thanks for this, it compiles, the event never fires but at least it compiles! – Apr 17 '14 at 15:18

parameter less constructor error

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