Autofac to inject dependency automatically using InjectProperties or manually resolve using Resolve<>

Question

I'm using Autofac in ASP.Net WebForm. According to the documentation, if I want to resolve dependencies in web controls, I'll need to use the following approach -

Dependency Injection via Base Page Class

public class MyWebControl : WebControl
{
   public IFirstService FirstService { get; set; }
   public ISecondService SecondService { get; set; }

   public MyWebControl()
   {        
      var cpa = (IContainerProviderAccessor)
           HttpContext.Current.ApplicationInstance;
      var cp = cpa.ContainerProvider;
      cp.RequestLifetime.InjectProperties(this);
   }
}

The above code work fine. However, in order to improve the speed, I'm thinking that I can resolve depedencies myself using the following approach.

public MyWebControl()
{        
   var cpa = (IContainerProviderAccessor)HttpContext.Current.ApplicationInstance;
   var cp = cpa.ContainerProvider;
   FirstService = cp.ApplicationContainer.Resolve<IFirstService>();
   SecondService = cp.ApplicationContainer.Resolve<ISecondService>();
}

Please correct me if I'm wrong. I doubt that it is a Service Locator pattern (Mark Seemann said Service Locator is an Anti-Pattern in Dependency Injection in .NET book ).

Question

Should I use the first approach or second?

Answer 1

I'd say use the first approach. The least knowledge your code has on the actual container the better. You should only care about your dependencies.