How to ignore Event class member for binary serialization?

Paul Sasik picture Paul Sasik · Mar 5, 2010 · Viewed 7.6k times · Source

I need to avoid serializing an Event class member because when the event is handled by an object that is not marked as Serializable the serialization will fail.

I tried using the NonSerialized attribute on the Event class member but it fails to compile. This line of code:

<NonSerialized()> Public Event PropertyValueChanged()

produces the following error:

Attribute 'NonSerializedAttribute' cannot be applied to 'PropertyValueChanged' because the attribute is not valid on this declaration type.

Public Event PropertyValueChanged() ' compiles but needs the extra handling described below

Is there another way to avoid serializing Event members?

This is not a problem if the event is not handled and I can work around it by cloning the objects (and ignoring the event) before serializing them. Just wondering if there is a better way.

Thanks.

Answer

Marc Gravell picture Marc Gravell · Mar 5, 2010

In C# you can do this as below, so I hope this translates identically to VB.

Note this only applies to field-like events (i.e. where you don't have your own add/remove):

[field: NonSerialized]
public event EventType EventName;

Otherwise something like:

[NonSerialized]
EventType backingField;
public event EventType {
    add { backingField += value; }
    remove { backingField -= value; }
}