Question

I’m trying to follow some example in learning sorting arrays. Example use Id as integer to sort by this property, since my object use Guid datatype instead of int I’m decided to use Created DateTime property to sort array. Here’s the code

Car.cs
    public class Car:ICar,IComparable
    {
       ... properties
       int IComparable.CompareTo(object)
       {
          Car temp = obj as Car;
          if (temp != null)
          {
             if (this.Created > temp.Created)
                return 1;
             if (this.Created < temp.Created)
                return -1;
            else 
                return 0;
          }
          else {throw new ArgumentException("Parameter is not a Car object");}
       }
    }

Garage.cs

public class Garage : IEnumerable
    {
        private Car[] cars = new Car[4];

        public Garage()
        {
            cars[0] = new Car() { Id = Guid.NewGuid(), Name = "Corolla", Created = DateTime.UtcNow.AddHours(3), CurrentSpeed = 90 };
            cars[1] = new Car() { Id = Guid.NewGuid(), Name = "Mazda", Created = DateTime.UtcNow.AddHours(2), CurrentSpeed = 80 };
        }
       ...
}

Program.cs

 static void Main(string[] args)
        {
           Garage cars = new Garage();
           Console.WriteLine("sorting array:");
           Array.Sort(cars); // error occured
        }

Error 2 Argument 1: cannot convert from ‘Car’ to ‘System.Array’

Answer 1

This solution assumes you want to sort the array in place, and not create a new one.

To your Garage class, add a method (so you don’t have to expose the inner array):

public void Sort() {
    Array.Sort(cars);
}

Then call this method from your program:

static void Main(string[] args)
{
    Garage garage = new Garage();
    garage.Sort();
    //It should be sorted now if you enumerate over it!
}

I’ve taken the liberty of calling your Garage object garage rather than cars which can be confusing.

I haven’t tested this, but it’s so straightforward, that it should work.