设计模式_策略模式

/// <summary>
/// 抽象算法
/// </summary>
public abstract class Strategy
{
    public abstract void AlgorithmInterface();
}

public class ConcreteStrategyA : Strategy
{
    public override void AlgorithmInterface()
    {
        Console.WriteLine("算法A实现");
    }
}
public class ConcreteStrategyB : Strategy
{
    public override void AlgorithmInterface()
    {
        Console.WriteLine("算法B实现");
    }
}
public class ConcreteStrategyC : Strategy
{
    public override void AlgorithmInterface()
    {
        Console.WriteLine("算法C实现");
    }
}

public class Context
{
    Strategy _strategy;
    /// <summary>
    /// 初始化时，传入具体的策略对象
    /// </summary>
    /// <param name="strategy"></param>
    public Context(Strategy strategy)
    {
        _strategy = strategy;
    }
    public void ContextInterface()
    {
        _strategy.AlgorithmInterface();
    }
}

 static void Main(string[] args)
 {
     Console.WriteLine("Hello World!");
     /*
      * 商场促销---策略模式
      */
     //策略模式（Strategy）:它定义了算法家族，分别封装起来，让它们之前可以互相替换，此模式让算法的变化，不会影响到使用算法的客户
     Context context;
     context = new Context(new ConcreteStrategyA());
     context.ContextInterface();

     context = new Context(new ConcreteStrategyB());
     context.ContextInterface();

     context = new Context(new ConcreteStrategyC());
     context.ContextInterface();

     Console.Read();
 }