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c#listcloneautomappervalueinjecter

How to deep clone objects containing an IList property using AutoMapper


I am trying to deep clone the following class using AutoMapper:

public class MainData
{
    public MainData()
    {
        Details = new List<Detail>();
    }

    public int Id { get; private set; }
    public DateTime LastUpdate { get; private set; }
    public IList<Detail> Details { get; private set; }
    public int Prop1 { get; set; }
    public int Prop2 { get; set; }

    public void AddDetail(Detail detail)
    {
        Details.Add(detail);
    }

    public void RemoveDetail(Detail detail)
    {
        Details.Remove(detail);
    }

    public MainData Clone()
    {
        Mapper.Reset();
        Mapper.CreateMap<MainData, MainData>().ForMember(d => d.Id, o => o.Ignore());
        // Mapper.CreateMap<Detail, Detail>().ForMember(d => d.Id, o => o.Ignore()); // REMOVED
        var newMainData = new MainData();
        Mapper.Map(this, newMainData);
        newMainData.Details = this.Details.Select(item => item.Clone()).ToList(); // ADDED
        return newMainData;
    }
}

public class Detail
{
    public int Id { get; private set; }
    public string Name { get; set; }
    public double Area { get; set; }
    public double Height { get; set; }

    public Detail Clone() // ADDED
    {
        Mapper.CreateMap<Detail, Detail>().ForMember(d => d.Id, o => o.Ignore());
        var newDetail = new Detail();
        Mapper.Map(this, newDetail);
        return newDetail;
    }
}

The Clone method works fine for the MainData properties but seems to only do a shallow copy of the Details list. I have tried adding .ForMember(d => d.Details, o => o.UseDestinationValue()) but this does not copy the Details list at all. How can I get the Details list deep cloned as well ie, so I end up with two totally independent objects including all the list items?

UPDATE: I need to exclude the Id property as I am using these objects with NHibernate so not sure if the Serializable solution will do this.

UPDATE2: Modified the above code to clone the IList too. This seems to work fine as I can exclude properties that make NHibernate think it has already been saved.


Solution

  • here is one solution with the ValueInjecter

            var clone = new MainData();
    
            clone.InjectFrom(mainData);//mainData is your source
    
            mainData.Details.AsParallel.ForAll(detail => 
            {
                var dc = new Detail();
                dc.InjectFrom(detail);
                clone.AddDetail(dc);
            });
    

    the properties that have private setters are not going to be set, (looks reasonable)
    good luck ;)

    EDIT: I did a better solution look here