How can I pass a runtime parameter as part of the dependency resolution?

Question

I need to be able to pass a connection string into some of my service implementations. I am doing this in the constructor. The connection string is configurable by user will be

Answer 1

Further to @Tseng's extremely helpful answer, I found I could also adapt it to use delegates:

public delegate INestedService INestedServiceFactory(string connectionString);

services.AddTransient((provider) => new INestedServiceFactory(
    (connectionString) => new NestedService(connectionString)
));

Implemented in RootService in the same way @Tseng suggested:

public class RootService : IRootService
{
    public INestedService NestedService { get; set; }

    public RootService(INestedServiceFactory nestedServiceFactory)
    {
        NestedService = nestedServiceFactory("ConnectionStringHere");
    }

    public void DoSomething()
    {
        // implement
    }
}

I prefer this approach for cases where I need an instance of a factory in a class, as it means I can have a property of type INestedServiceFactory rather than Func.