Microsoft.Practices.Unity

//
// Summary:
// Register a type mapping with the container.
//
// Parameters:
// container:
// Container to configure.
//
// injectionMembers:
// Injection configuration objects.
//
// Type parameters:
// TFrom:
// System.Type that will be requested.
//
// TTo:
// System.Type that will actually be returned.
//
// Returns:
// The Microsoft.Practices.Unity.UnityContainer object that this method was called
// on (this in C#, Me in Visual Basic).
//
// Remarks:
// This method is used to tell the container that when asked for type TFrom, actually
// return an instance of type TTo. This is very useful for getting instances of
// interfaces.
// This overload registers a default mapping and transient lifetime.
[SuppressMessage("Microsoft.Design", "CA1004:GenericMethodsShouldProvideTypeParameter", Justification = "As designed")]
public static IUnityContainer RegisterType<TFrom, TTo>(this IUnityContainer container, params InjectionMember[] injectionMembers) where TTo : TFrom;

class Program
{
static UnityContainer container = new UnityContainer();

static void Init()
{
container.RegisterType<IPlayer, Player>();
container.RegisterType<IMediaFile, MediaFile>();
}
static void Main(string[] args)
{
Init();
OperationMain op1 = container.Resolve<OperationMain>();
op1.PlayMedia();
Console.ReadLine();
}
}

//媒体文件
public interface IMediaFile
{
string FilePath { get; set; }
}

//默认媒体文件
public class MediaFile : IMediaFile
{
private string filePath;
public string FilePath
{
get
{
return filePath;
}
set
{
filePath = value;
}
}
}

//播放器
public interface IPlayer
{
void Play(IMediaFile file);
}

//默认播放器
public class Player : IPlayer
{
public void Play(IMediaFile file)
{
Console.WriteLine(file.FilePath);
}
}

public class OperationMain
{
IMediaFile _mtype;
IPlayer _player;

public OperationMain(IPlayer player,IMediaFile mtype)
{
_player = player;
_mtype = mtype;
}

public void PlayMedia()
{
_player.Play(_mtype);
}
}