Mapping List`1 to Object properties

Question

I have a structure defined

public class FullIndexList
{
    public IList<IndexCurrency> IndexCurrency { get; set; }

    public IList<Indices> Indices { get; set; }
 }

The List returned from the method

So basically the list items are properties FullIndexList ,the type is List`1

I want to convert the result to FullIndexList.

I have tried using cast as results.Cast() it givens error as invalid cast, I have also tried using results.ConvertAll but in that case I need to hard code like this

fullIndexList.IndexCurrency = results[0] as IList<IndexCurrency>;
fullIndexList.Indices = results[1] as IList<Indices>;

which does not looks right.

I can think of using Reflection or Automapper but I believe there might be a better way of doing this.

Try : fullIndexList.IndexCurrency.AddRange(results[0].Select(x => (IndexCurrency)x).ToList()); — jdweng, Oct 21 '16 at 07:52
I do not want to hard code indexes of result else fullIndexList.IndexCurrency = results[0] as IList; is more friendly — Rahul, Oct 21 '16 at 08:12
*The List returned from the method* What is the type of "the list" and what is "the method"? Why don't you create `FullIndexList` objects right away in "the method"? — Gert Arnold, Oct 22 '16 at 09:33

score 0 · Answer 1 · edited May 23 '17 at 10:32

0

This makes your result flat and then find the type to make IList.

var flat = results.OfType<IEnumerable<object>>().SelectMany((x) => x).ToArray();
fullIndexList.IndexCurrency = flat.OfType<IndexCurrency>().ToList();
fullIndexList.Indices = flat.OfType<Indices>().ToList();

Your results is List<dynamic> so need to cast it to IEnumerable<object> or any other common base class or interface. This means if your IndexCurrency or Indices is struct, it's difficult. Struct cannot be casted directly to object. Why cannot IEnumerable<struct> be cast as IEnumerable<object>?

If you can make results not to use dynamic, it becomes very easy because you can directly make it flat by SelectMany().

edited May 23 '17 at 10:32

Community

1
1

answered Oct 21 '16 at 08:54

cactuaroid

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Error 26 The type arguments for method 'System.Linq.Enumerable.SelectMany(System.Collections.Generic.IEnumerable, System.Func>)' cannot be inferred from the usage. Try specifying the type arguments explicitly. – Rahul Oct 21 '16 at 09:20
@Rahul What is the type of `results`, `results[0]` and `results[1]`? I assumed they are `List>` and `List – cactuaroid Oct 21 '16 at 16:23
result is List`1 and results[0] List , results[1] List – Rahul Oct 21 '16 at 17:10
@Rahul Oh you mean `results` is `List` type. `IndexCurrency` and `Indices` are class or struct? – cactuaroid Oct 21 '16 at 20:44

score 0 · Accepted Answer · answered Nov 07 '16 at 10:03

I was able to get it done using zip and tupple.

foreach (var tuple in typeof(FullIndexList).GetProperties().Zip(results, Tuple.Create))
{
   tuple.Item1.SetValue(full, tuple.Item2, null);
}

where FullIndexList is the container type.

However I am not performing any check and assuming the order and no of items in both list are exactly same.

Mapping List`1 to Object properties

2 Answers2