IEnumerable.Cast won't work even if an explicit cast operator is defined?

Question

I have an explicit conversion defined from type Bar to type Foo.

public class Bar
{
  public static explicit operator Foo(Bar bar)
         


        

Answer 1

Your code doesn't actually compile. I assume that there is a property "Gar" in the "Bar" class as well?

public class Bar
    {
        public string Gar { get; set; }

        public static explicit operator Foo(Bar bar)
        {
            return new Foo(bar.Gar);
        }
    }

    public class Foo
    {
        public string Gar { get; set; }

        public Foo() { }

        public Foo(string gar) { Gar = gar; }
    }

static void Main(string[] args)
        {

            List bars = new List();
            for (int i = 0; i < 10; i++)
                bars.Add(new Bar() { Gar = i.ToString() });

            var result = bars.Cast();
        }

+

I encaurage you to read about covariance.

Assuming A is convertible to B, X is covariant if X is convertible to X.

With C#’s notion of covariance (and contravariance), “convertible” means convertible via an implicit reference conversion— such as A subclassing B, or A implementing B. Numeric conversions, boxing conversions, and custom conversions are not included.

You have to do that with interfaces.