C#设计模式/Factory Method模式

封装对象创建的变化
类LogFactory是所有工厂类的抽象父类,专门负责Log对象的创建.

Code:

public abstract class Log
    {
        public abstract void Write(string target, string logValue);
    }
public class DBLog:Log
    {
        public override void Write(string target, string logValue)
        {
            Console.WriteLine("Logging {0} to DB {1}.", logValue, target);
        }
    }
public abstract class LogFactory
    {
        public abstract Log Create();
    }
public class DBLogFactory:LogFactory
    {
        public override Log Create()
        {
            return new DBLog();
        }
    }
class Program
    {
        static void Main(string[] args)
        {
            LogFactory factory = new DBLogFactory();
            Log lg = factory.Create();
            lg.Write("DBLogFactory", "DBLogFactoryValue");
            Console.ReadLine();
        }
    }