Façade design pattern example

gistfile1.cs

public class UserManager
{
	// The main implementation of IRepository would be internal to your Core/Domain project,
	// so consumers of your API couldn't change the database directlry without going through
	// your façade classes.
	private IRepository _repository;
	
	public UserManager()
	{
		_repository = new SqlRepository("some connection string from a config file");
	}
	
	public UserManager(IRepository repository)
	{
		_repository = repository;
	}
	
	public User GetById(Guid id)
	{
		return _repository.ExecuteSql<User>("SELECT * FROM User WHERE Id=@Id", id)
	}
	
	public User GetByEmail(string email)
	{
		return _repository.ExecuteSql<User>("SELECT * FROM User WHERE Email=@Email", email)
	}
	
	// more methods User-specific methods.
}