如何在不同的Winform之间进行通信

Question

I have a container WinForm called frmMain which holds another forms like frmOrder , frmMessage , the subforms was added in a TabPage control.

What I want to do is communicating between subforms, say user changes something in frmOrder and frmMessage need to be notified, currently I think the communication need to be delegated through the frmMain .

One solution I can think is to make subforms deriving from my custom Form derived class which defines interface say:

public class MessageEnabledForm: Form 
{
    public void SendMessage(String destFormName, String messageType, String data);
    public void ReceiveMessage(String destFormName, String messageType, String data);
}

I don't know whether this is feasible, and is there any other solutions I can employ? which is generic and needn't to know the concrete subform.

Answer 1

Based on your question, I don't think inheritance is the best tool for the job. I say its not the best choice because you are not dealing with an "is a" relationship. I think you should consider using Events and Delegates to handle the communication between forms and subforms. The following MSDN article provides a good overview of Handling and Raising Events . You also may want to refresh yourself on the .NET INotifyPropertyChanged Interface if you using data binding in the subforms.

Answer 2

You could use an Interface like this, that all the child forms implement:

public interface Communication
{
    public delegate void SendMessageDelegate(String destFormName, String messageType, String data);
    public event SendMessageDelegate SendMessage;

    public void ReceiveMessage(String destFormName, String messageType, String data);
}

When the main form receives the event, it can iterate over its "child" forms looking for a match on destFormName then call its ReceiveMessage() implementation (after casting it to the Communication interface).