Serialization of a class with events

Question

I have a Class like this:

public delegate void ChangedEventHandler(object sender, EventArgs e); [Serializable] public class valueDouble {     public event ChangedEventHandler Changed;     public double value     {         get { return _value; }         set          {             _value = value;             if (Changed != null)             {                 Changed(this, EventArgs.Empty);             }         }     }     private double _value = 0; } 

I also have another Class (StepPulseblaster) which is not serializable and adds an Event Handler

valDouble.Changed += new ChangedEventHandler(sc_PropertyChanged); 

When i try to serialize the valueDouble Class, there will be an error:

The Type StepPulseblaster is not marked as serializable 

When i comment the line

valDouble.Changed += ... 

there will be no error any more.

How can i serialize a class which has some events connected?

Answer 1

You should do:

[field: NonSerialized] public event ChangedEventHandler Changed; 

As described in the MSDN:

To apply the NonSerializedAttribute class to an event, set the attribute location to field.

Answer 2

The NonSerialized attribute is only available for fields, so to use it you have to adjust your code to use fields.

Try creating your event like this:

[NonSerialized] private ChangedEventHandler _changed; public event ChangedEventHandler Changed {     add { _changed += value; }     remove { _changed -= value; } } 

Then in the value property use the field, not the property:

public double value {     get { return _value; }     set      {         _value = value;         if (_changed != null)         {             _changed(this, EventArgs.Empty);         }     } } private double _value = 0;