Strategy設計模式定義了一系列算法，分別封裝起來，并使它們之間可以互相替換。此模式允許讓算法得變化獨立于使用它得客戶。
OO設計原則策略模型類圖
代碼namespace DesignPattern.Strategy.Structural{ /// <summary> /// The 'Context' class /// </summary> public class Context { Strategy strategy; public Context(Strategy strategy) { this.strategy = strategy; } public void ContextInterface() { strategy.AlgorithmInterface(); } } /// <summary> /// The 'Strategy' class /// </summary> public abstract class Strategy { public abstract void AlgorithmInterface(); } /// <summary> /// The 'StrategyA' class /// </summary> public class StrategyA: Strategy { public override void AlgorithmInterface() { Console.WriteLine("ConcreteStrategyA AlgorithmInterface."); } } /// <summary> /// The 'StrategyB' class /// </summary> public class StrategyB : Strategy { public override void AlgorithmInterface() { Console.WriteLine("ConcreteStrategyB.AlgorithmInterface."); } } /// <summary> /// The 'StrategyC' class /// </summary> public class StrategyC : Strategy { public override void AlgorithmInterface() { Console.WriteLine("ConcreteStrategyC.AlgorithmInterface."); } } /// <summary> /// MainApp startup class for Structural /// </summary> public class Program { private static void Main(string[] args) { Context context; context = new Context(new StrategyA()); context.ContextInterface(); context = new Context(new StrategyB()); context.ContextInterface(); context = new Context(new StrategyC()); context.ContextInterface(); } }}
輸出結果
ConcreteStrategyA AlgorithmInterface.ConcreteStrategyB.AlgorithmInterface.ConcreteStrategyC.AlgorithmInterface.
