Making interface implementations async

Question

I’m currently trying to make my application using some Async methods. All my IO is done through explicit implementations of an interface and I am a bit confused about how to

Answer 1

An abstract class can be used instead of an interface (in C# 7.3).

// Like interface
abstract class IIO
{
    public virtual async Task DoOperation(string Name)
    {
        throw new NotImplementedException(); // throwing exception
        // return await Task.Run(() => { return ""; }); // or empty do
    }
}

// Implementation
class IOImplementation : IIO
{
    public override async Task DoOperation(string Name)
    {
        return await await Task.Run(() =>
        {
            if(Name == "Spiderman")
                return "ok";
            return "cancel";
        }); 
    }
}