How to use C# object from F#?

Question

I have the following C# code.

namespace MyMath {
    public class Arith {
        public Arith() {}
        public int Add(int x, int y) {
            return         


        

Answer 1

try

open MyMath
let arith = Arith() // create instance of Arith
let x = arith.Add(10, 20) // call method Add

Arith in your code is class name, you cannot open it like namespace. Possibly you are confused with ability to open F# modules so its functions can be used without qualification