using System.Linq;

public class Program

{

    public static void Main()

    {

        IShipmentList shipmentList = null;

        shipmentList.ToArray();

    }

}

​

interface IShipmentList

{

    IShipment this[int i] { get; }

    int ShipmentCount { get; }

}

​

interface IShipment

{

}

​

static class ToArrayExtension

{

    public static IShipment[] ToArray(this IShipmentList self)

    {

        IShipment[] result = new IShipment[self.ShipmentCount];

        for(int index = 0; index < self.ShipmentCount; index ++)

        {

            result[index] = self[index];

        }

        return result;

    }

}