C#C
C#•3y ago
Determinism

❔ Generic factory with dependency injection

Hello,

I am trying to create a generic factory. However, I don't want to pass T as it creates much more boilerplate code:

internal static class MonitoredValueInstanceFactoryExtension
{
    public static void AddMonitoredValueInstanceFactory<T>(this IServiceCollection services)
    {
        services.AddTransient<IMonitoredValue<T>, MonitoredValue<T>>();
        services.AddTransient<Func<IMonitoredValue<T>>>(x => x.GetRequiredService<IMonitoredValue<T>>);
        services.AddSingleton<IMonitoredValueInstanceFactory<T>, MonitoredValueInstanceFactory<T>>();
    }
}

internal sealed class MonitoredValueInstanceFactory<T> : IMonitoredValueInstanceFactory<T>
{
    private readonly Func<IMonitoredValue<T>> _factory;

    public MonitoredValueInstanceFactory(Func<IMonitoredValue<T>> factory)
    {
        _factory = factory;
    }

    public IMonitoredValue<T> Create(string location, Subscription sub, ushort namespaceIndex = 2, bool callbackOnInitialize = true)
    {
        var factory = _factory();

        MonitoredValue<T> mi = new(sub.DefaultItem)
        {
            DisplayName = location,
            StartNodeId = new NodeId(location, namespaceIndex),
            CallbackOnInitialize = callbackOnInitialize
        };

        sub.AddItem(mi);

        return factory;
    }
}

// Program.cs, how it currently needs to be called
        services.AddMonitoredValueInstanceFactory<string>();
        services.AddMonitoredValueInstanceFactory<float>();
        services.AddMonitoredValueInstanceFactory<int>();
        services.AddMonitoredValueInstanceFactory<short>();
        services.AddMonitoredValueInstanceFactory<bool>();
        services.AddMonitoredValueInstanceFactory<ushort>();


// I would prefer to call it like this with no type
services.AddMonitoredValueInstanceFactory();


Is this something that is possible?
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