NopCommerce源码分析ContainerBuilder builder.Update(container)

/// <summary>
/// Register dependencies
/// </summary>
/// <param name="config">Config</param>
protected virtual void RegisterDependencies(NopConfig config)
{
var builder = new ContainerBuilder();
var container = builder.Build();
this._containerManager = new ContainerManager(container);

//we create new instance of ContainerBuilder
//because Build() or Update() method can only be called once on a ContainerBuilder.

//dependencies
var typeFinder = new WebAppTypeFinder();
builder = new ContainerBuilder();
builder.RegisterInstance(config).As<NopConfig>().SingleInstance();
builder.RegisterInstance(this).As<IEngine>().SingleInstance();
builder.RegisterInstance(typeFinder).As<ITypeFinder>().SingleInstance();
builder.Update(container);

//register dependencies provided by other assemblies
builder = new ContainerBuilder();
var drTypes = typeFinder.FindClassesOfType<IDependencyRegistrar>();
var drInstances = new List<IDependencyRegistrar>();
foreach (var drType in drTypes)
drInstances.Add((IDependencyRegistrar) Activator.CreateInstance(drType));
//sort
drInstances = drInstances.AsQueryable().OrderBy(t => t.Order).ToList();
foreach (var dependencyRegistrar in drInstances)
dependencyRegistrar.Register(builder, typeFinder, config);
builder.Update(container);

//set dependency resolver
DependencyResolver.SetResolver(new AutofacDependencyResolver(container));
}

#endregion