ASP.NET Web Services Dependency Injection using Unity

//===============================================================================
// PnPGuidance.net
// Unity IoC and ASP.NET Demo
//-------------------------------------------------------------------------------
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// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY
// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT
// LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
// FITNESS FOR A PARTICULAR PURPOSE.
//-------------------------------------------------------------------------------
// The example companies, organizations, products, domain names,
// e-mail addresses, logos, people, places, and events depicted
// herein are fictitious.  No association with any real company,
// organization, product, domain name, email address, logo, person,
// places, or events is intended or should be inferred.
//===============================================================================
using System;
using System.Web;
using System.Web.UI;
using Microsoft.Practices.Unity;

namespace Unity.Services
{
	public abstract class BaseService<T> : System.Web.Services.WebService where T : class
    {
		public BaseService()
        {
            InjectDependencies();
        }

        protected virtual void InjectDependencies()
        {
            HttpContext context = HttpContext.Current;

            if (context == null)
                return;

            IContainerAccessor accessor = context.ApplicationInstance as IContainerAccessor;

            if (accessor == null)
                return;

            IUnityContainer container = accessor.Container;

            if (container == null)
                throw new InvalidOperationException("Container on Global Application Class is Null. Cannot perform BuildUp.");

            container.BuildUp(this as T);
        }
    }
}