How to make a custom mapping from a csv column to some custom code?

Question

I have generated entities classes (like MyClass), and I need to read a csv file, and then return a List of MyClass. On all entities, we have a readonly property CreateOn. To set the CreatedOn, we need to do this custom code : Attributes["overriddencreatedon"] = DateTime.Now;

Is it possible with CsvHelper to do something like this ? :

public class MyClass // in real life, inherits from  Microsoft.Xrm.Sdk.Entity
{
    public Guid Id { get; set; }
    public DateTime CreatedOn { get;} // Readonly because generated class...
    public Dictionary<string, object> Attributes { get; set; }
}

private class MyClassMap : ClassMap<MyClass>
{
    public MyClassMap()
    {
        Map(f => f.Id).Name("Id");
        // Cannot do this : Map(f => f.CreatedOn).Name("CreatedOn");
        // Because CreatedOn is readonly
        // The goal is to store the value in the dictionary Attributes, not in the property CreatedOn because it is readonly
        // Instead, we need to do something like this:
        Map().XXX((row, x) => x.Attributes["overriddencreatedon"] = row.Row.GetField<DateTime>("CreatedOn"));
    }
}

Answer 1

This should work for Dictionary<string, object> Attributes.

Map(f => f.Attributes).Convert(args =>
{
    return new Dictionary<string, object> {
        { "overriddencreatedon", args.Row.GetField<DateTime>("CreatedOn") }
    };
});

If MyClass inherits from Microsoft.Xrm.Sdk.Entity then it should be AttributeCollection Attributes.

Map(f => f.Attributes).Convert(args =>
{
    return new AttributeCollection {
        { "overriddencreatedon", args.Row.GetField<DateTime>("CreatedOn") }
    };
});