Base Virtual Method not called or called twice

Question

Here my code.

public class EventItem
{
    public int Id { get; set; } = -1;
    public int ClientId { get; set; }

    public EventItem(IDataRecord rdr)
    {
        FillAttributs(rdr);
    }

    public virtual void FillAttributs(IDataRecord rdr)
    {
        this.Id = (int)rdr["EventId"];
        this.ClientId = (int)rdr["ClientId"];
    }
}

public class ControlItem : EventItem
{
    public int ControlId { get; set; }

    public ControlItem(IDataRecord rdr) : base(rdr)
    {
        FillAttributs(rdr);
    }

    public override void FillAttributs(IDataRecord rdr)
    {
        base.FillAttributs(rdr); // Version 1
        this.ControlId = (int)rdr["ControlId"];
    }
}
...
ControlItem ctrl = new ControlItem(rdr)

Version 1 : With base.FillAttributs(rdr), FillAttributs of base class and child class are called twice. Without, only FillAttributs of child class is called twice.

Version 2 : I remove base.FillAttributs(rdr), virtual and replace override with public new void FillAttributs(IDataRecord rdr). So It works but I'm not sure if it's a good practice.

Version 3 : I rename FillAttributs of base class to FillEventAttributs and of chil class to FillControlAttributs.

what is the right way to go here ? Or should I use another way to do it ?

Answer 1

Remove FillAttributs(rdr) from ControlItem constructor. its look like this:

public class EventItem
{
public int Id { get; set; } = -1;
public int ClientId { get; set; }

public EventItem(IDataRecord rdr)
{
    FillAttributs(rdr);
}

public virtual void FillAttributs(IDataRecord rdr)
{
    this.Id = (int)rdr["EventId"];
    this.ClientId = (int)rdr["ClientId"];
}
}

public class ControlItem : EventItem
{
public int ControlId { get; set; }

public ControlItem(IDataRecord rdr) : base(rdr)
{
    //FillAttributs(rdr);
}

public override void FillAttributs(IDataRecord rdr)
{
    base.FillAttributs(rdr); // Version 1
    this.ControlId = (int)rdr["ControlId"];
}
}
...
ControlItem ctrl = new ControlItem(rdr)

Now base and derived called once. I hope this help you.