UnityAssemblyExtensions.cs

UnityAssemblyExtensions.cs

public static class UnityAssemblyExtensions
{
	public static IUnityContainer RegisterTypesFromAssembliesInBasePath<T>(this IUnityContainer container)
	{
		var types = FromAssembliesInBasePath<T>();
		foreach (var t in types)
		{
			container.RegisterType(typeof(T), t, t.FullName);
		}

		return container;
	}

	private static IEnumerable<Type> FromAssembliesInBasePath<T>()
	{
		return FromCheckedAssemblies<T>(GetAssembliesInBasePath<T>());
	}

	private static IEnumerable<Type> FromCheckedAssemblies<T>(IEnumerable<Assembly> assemblies)
	{
		return assemblies.SelectMany(a => a.DefinedTypes
										   .Where(ti => ti.IsClass & !ti.IsAbstract && !ti.IsValueType && ti.IsVisible && IsInheritedFromInterface<T>(ti.AsType()))
										   .Select(ti => ti.AsType()));
	}

	private static IEnumerable<Assembly> GetAssembliesInBasePath<T>()
	{
		return Directory.EnumerateFiles(AppDomain.CurrentDomain.BaseDirectory, "*.dll")
						.Select(a => LoadAssembly(Path.GetFileNameWithoutExtension(a)))
						.Where(a => a != null && !IsSystemAssembly(a) && !IsUnityAssembly(a) && ContainsType<T>(a));
	}

	private static Assembly LoadAssembly(string assemblyName)
	{
		try
		{
			return Assembly.Load(assemblyName);
		}
		catch 
		{
			return null;
		}
	}

	private static bool ContainsType<T>(Assembly assembly)
	{
		if (assembly == null)
			return false;

		return assembly.DefinedTypes.Select(t => t.AsType())
									.Where(t => IsInheritedFromInterface<T>(t))
									.ToArray()
									.Length > 0;
	}

	private static bool IsInheritedFromInterface<T>(Type type)
	{
		if (type == null)
			return false;

		return type.FindInterfaces((m, f) => m == typeof(T), null).Length > 0;
	}

	private static bool IsSystemAssembly(Assembly assembly)
	{
		if (assembly == null)
			return false;

		var netFrameworkProductName = GetNetFrameworkProductName();
		if (netFrameworkProductName != null)
		{
			var productAttribute = assembly.GetCustomAttribute<AssemblyProductAttribute>();
			return productAttribute != null && string.Compare(netFrameworkProductName, productAttribute.Product, StringComparison.Ordinal) == 0;
		}
		else
		{
			return false;
		}
	}

	private static bool IsUnityAssembly(Assembly assembly)
	{
		if (assembly == null)
			return false;

		var unityProductName = GetUnityProductName();
		if (unityProductName != null)
		{
			var productAttribute = assembly.GetCustomAttribute<AssemblyProductAttribute>();
			return productAttribute != null && string.Compare(unityProductName, productAttribute.Product, StringComparison.Ordinal) == 0;
		}
		else
		{
			return false;
		}
	}

	private static string GetNetFrameworkProductName()
	{
		var productAttribute = typeof(object).GetTypeInfo().Assembly.GetCustomAttribute<AssemblyProductAttribute>();
		return productAttribute != null ? productAttribute.Product : null;
	}

	private static string GetUnityProductName()
	{
		var productAttribute = typeof(AllClasses).GetTypeInfo().Assembly.GetCustomAttribute<AssemblyProductAttribute>();
		return productAttribute != null ? productAttribute.Product : null;
	}
}