NPOCO: Why is my custom Mapper not called

Question

In one of my entities I need a special mapping which converts a delimited string (from the DB) to a Dictionary. Instead of using some dummy property I thought the more elegant way would be a custom mapper as described here

My problem is that no method from the mapper is ever called and NPOCO attempts to convert my db-string to a dictionary which obviously fails.

Maybe I misunderstand the mapper or am missing something. But can't explain why it doesn't work.

My Mapping (simplified)

public class MyEntityMap : Map<MyEntity>
{
    public MyEntity()
    {
        Columns(x =>
            {   
              x.Column(c => c.SpecialColumn).WithName("SpecialColumn");
            }, true);
    }
}

My Mapper (doesn't do much)

public class MyMapper : DefaultMapper
{
    public override Func<object, object> GetFromDbConverter(MemberInfo destMemberInfo, Type sourceType)
    {
        return base.GetFromDbConverter(destMemberInfo, sourceType);
    }

    public override Func<object, object> GetFromDbConverter(Type destType, Type sourceType)
    {
        return base.GetFromDbConverter(destType, sourceType);
    }

    public override bool MapMemberToColumn(MemberInfo pi, ref string columnName, ref bool resultColumn)
    {
        return base.MapMemberToColumn(pi, ref columnName, ref resultColumn);
    }

    public override void GetTableInfo(Type t, TableInfo ti)
    {
        base.GetTableInfo(t, ti);
    }
}

My datalayer (constructor)

protected SimpleDepot()            
    {
        //SQL Server / MySQL
        if (!mappingInitialized)
        {
            NPocoDatabaseFactory.Setup("connectionstring");
            mappingInitialized = true;
        }

        Database = NPocoDatabaseFactory.DbFactory.GetDatabase();
        Database.Mapper = new MyMapper();

        PocoData = Database.PocoDataFactory.ForType(typeof(TEntity));
    }

So everything seems in order at least to me. Any ideas what I'm missing. I'm currently using NPOCO 2.9.103 but I'm checking if I can update to v3

Answer 1

Ok, so I just upgraded to NPoco v3 and it went smoother than suspected (just had to change some small code parts to match breaking changes)

see https://github.com/schotime/NPoco/wiki/Version-3 for breaking changes.

Anyway: with v3 my mapper gets called. Maybe it was a bug in v2?

If you have the same problem with v2 consider upgrading to v3 (there are breaking changes which may or may not affect you)

I'm currently using v3.4.1