属性很多时如何很清晰的通过充血模型创建数据合法的对象

原因：在构建充血模型时，为构建合法的对象，对象赋值都在私有的。属性少的时候可以直接写构造函数，属性多时就不太合适了。

如何解决这个问题呢？代码如下

Book类：

public class Book
    {
        public long Id { get; private set; }
        public long AuthorId { get; private set; }
        public string Name { get; private set; }
        public string Code { get; private set; }
        public DateTime PubTime { get; private set; }
        public string Publisher { get; private set; }

        private Book()
        {

        }

        /// <summary>
        /// 声明嵌套类型
        /// </summary>
        public class Builder
        {
            private long Id;
            private long AuthorId;
            private string Name;
            private string Code;
            private DateTime PubTime;
            private string Publisher;

            public Builder SetId(long id)
            {
                this.Id = id;
                return this;
            }
            public Builder SetName(string name)
            {
                this.Name = name;
                return this;
            }
            public Builder SetAuthorId(long authorId)
            {
                this.AuthorId = authorId;
                return this;
            }
            public Builder SetCode(string code)
            {
                this.Code = code;
                return this;
            }
            public Builder SetPubTime(DateTime pubTime)
            {
                this.PubTime = pubTime;
                return this;
            }
            public Builder SetPublisher(string publisher)
            {
                this.Publisher = publisher;
                return this;
            }
            public Book Build()
            {
                if (Id == 0)
                {
                    throw new ArgumentNullException("id");
                }
                if (AuthorId == 0)
                {
                    throw new ArgumentNullException("AutorId");
                }
                var book = new Book();
                book.Id = Id;
                book.AuthorId = AuthorId;
                book.Name = Name;
                book.Code = Code;
                book.PubTime = PubTime;
                book.Publisher = Publisher;
                return book;
            }
        }
    }

//链式编程 构建合法的Book类
Book.Builder builder = new Book.Builder();
            var book = builder.SetId(1).SetAuthorId(1).SetCode("ddf").
                SetName("jisdjfoisjf").SetPublisher("122").SetPubTime(DateTime.Now)
                .Build();

数据校验都放在builder.Build方法中