ServiceCollectionSingletonBinding.cs

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using System;

namespace IoCContainer_net4_sharp5
{
    /// <summary>Simulates a Singleton - creates Implementation exactly once per ServiceCollectionSingletonBinding.</summary>
    public class ServiceCollectionSingletonBinding : ServiceCollectionBinding
    {
        public ServiceCollectionSingletonBinding(ServiceCollectionBinding binding = null)
            : base (binding) { }
        private object _instance = null;

        public override object Create(IInstanceBuilder builder, Type type, object[] args)
        {
            return _instance ?? (_instance = builder.Create (type, args));
        }

        /// <summary>Bind a service to this binding via its Interface and Implementation.</summary>
        public ServiceCollectionSingletonBinding Bind<Interface, Implementation>()
            where Interface : class
            where Implementation : class
        {
            this.Interface = new Type[] { typeof (Interface) };
            this.Implementation = new Type[] { typeof (Implementation) };
            return this;
        }
    }
}