摘要：
1、面向对象三大特性：封装、继承、多态；四大好处：可维护、可复用、可扩展、灵活性好。2、业务的封装：高内聚、低耦合。3、赋值！=复用。4、简单设计模式之工厂模式：类的泛化1 public class OperationFactory2 {3 public static Operation createOperate(string operate)4 {5 Operation oper = null;6 switch (operate)7 {8 case "+":9 {10 oper = new OperationAdd();11 break;12 }13 case "- 阅读全文
