Conditional dependency resolver on run-time (.net Core)

Question

I have two classes PaymentGatewayFoo, PaymentGatewayBoo that both implements a common interface of IPaymentGateway:

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Answer 1

After trying to implement the great answers here, it looks like that the native DI .net core container does not support injecting of numerables (like IPaymentGateway[] as @armand suggested) so I ended up with a delegate resolver based on switch case (not on reflection in order to save performance):

startup.cs

services.AddTransient(serviceProvider => key =>
{
    switch (key)
    {
        case E_PaymentGatewayType.Foo:
            return serviceProvider.GetService();
        case E_PaymentGatewayType.Boo:
            return serviceProvider.GetService();
        case E_PaymentGatewayType.Undefined:
            default:
            throw new NotSupportedException($"PaymentGatewayRepositoryResolver, key: {key}");
    }
});

The delegate:

public delegate IPaymentGateway PaymentGatewayResolver(E_PaymentGatewayType paymentGatewayType);

The client order service:

private readonly PaymentGatewayResolver _paymentGatewayResolver;

public OrderService(PaymentGatewayResolver paymentGatewayResolver)
{
    this._paymentGatewayResolver = paymentGatewayResolver; 
}

public DoOrder(E_PaymentGatewayType paymentGatewayType)
{
    IPaymentGateway paymentGateway = this._paymentGatewayResolver(paymentGatewayType);
    paymentGateway.Pay();
}