So I want to try to avoid using object in my methods to make things more type safe and avoid boxing/unboxing but I’m not sure what the best way to solve this is. Using generics is not ideal for this situation here since there will be a collection of the type (so it cannot have generic params). I’m thinking a solution that uses double dispatch might work here (i.e. visitor pattern).

The general setup is something along the lines of:

public class ServiceCheck(IList<IServiceCheckResult> results)
{
    public IList<IServiceCheckResult> Results = results;
}

public interface IServiceCheckResult
{
    IResultValidator Validator { get; }
    object? GetRawValue();
    void SetRawValue(object? value);
}

public class ServiceCheckResult(IResultValidator validator) : IServiceCheckResult
{
    private object? rawValue;
    public IResultValidator Validator { get; } = validator;

    public object? GetRawValue()
    {
        return rawValue;
    }

    public void SetRawValue(object? value)
    {
        rawValue = value;
    }
}

public interface IResultValidator
{
    public bool Validate(object? value);
}

public class StringValidator : IResultValidator
{
    public bool Validate(object? value)
    {
        return string.IsNullOrEmpty((string)value);
    }
}

public class DoubleValidator : IResultValidator
{
    public bool Validate(object? value)
    {
        return (double)value > 0;
    }
}

public class EnumValidator : IResultValidator
{
    public bool Validate(object? value)
    {
        return true;
    }
}
...

and the usage will be something like this:

var serviceCheck = new ServiceCheck(new List<IServiceCheckResult>
{
    new ServiceCheckResult(new DoubleValidator()),
    new ServiceCheckResult(new StringValidator()),
    new ServiceCheckResult(new EnumValidator())
});

serviceCheck.Results[0].SetRawValue(1.0);
serviceCheck.Results[1].SetRawValue("This is a test");
serviceCheck.Results[2].SetRawValue(MyEnum.None);

foreach (var result in serviceCheck.Results)
{
    var rawResult = result.GetRawValue();
    result.Validator.Validate(rawResult);
}