利用配置文件解耦工厂类型
定义一个接口
public interface IFactory { IProduct Create(); // 返回默认的 concrete product IProduct Create(string name); // 按照配置的逻辑名称返回指定的concrete product }
获取配置类
public class ProductRegistry { const string SectionName = "concreteProducts"; static NameValueCollection collection = (NameValueCollection)ConfigurationManager.GetSection(SectionName); public Type this[string name] { get { return Type.GetType(collection[name]); } } }
工厂
public class Factory : IFactory { public const string DefaultName = "DEFAULT"; public readonly ProductRegistry productRegistry = new ProductRegistry(); #region IFactory Members public IProduct Create() { return (IProduct)Activator.CreateInstance(productRegistry[DefaultName]); } public IProduct Create(string name) { if (string.IsNullOrEmpty(name)) throw new ArgumentNullException("name"); return (IProduct)Activator.CreateInstance(productRegistry[name]); } #endregion }
page 84,只为自己阅读,复习
如果批量生产的话
public interface IBatchFactory : IFactory { IEnumerable<IProduct> Create(string name, int quantity); IEnumerable<IProduct> Create(int quantity); }
public class BatchFactory : Factory, IBatchFactory { #region IBatchFactory Members /// <summary> /// batch create /// </summary> /// <param name="quantity"></param> /// <returns></returns> public IEnumerable<IProduct> Create(int quantity) { if (quantity <= 0) throw new IndexOutOfRangeException("quantity"); return InternalCreate<IProduct>(productRegistry[DefaultName], quantity); } /// <summary> /// batch create /// </summary> /// <param name="name"></param> /// <param name="quantity"></param> /// <returns></returns> public IEnumerable<IProduct> Create(string name, int quantity) { if (string.IsNullOrEmpty(name)) throw new ArgumentNullException("name"); return InternalCreate<IProduct>(productRegistry[name], quantity); } /// <summary> /// Helper method /// </summary> /// <typeparam name="T"></typeparam> /// <param name="type"></param> /// <param name="quantity"></param> /// <returns></returns> IEnumerable<T> InternalCreate<T>(Type type, int quantity) { if (quantity <= 0) throw new IndexOutOfRangeException("quantity"); if (type == null) throw new ArgumentNullException("type"); IList<T> result = new List<T>(); for (int i = 0; i < quantity; i++) result.Add((T)Activator.CreateInstance(type)); return result; } #endregion }
posted on 2013-03-28 13:10 HOT SUMMER 阅读(199) 评论(0) 编辑 收藏 举报