[1.理解抽象類的概念，為什么要有抽象類 ](%E7%90%86%E8%A7%A3%E6%8A%BD%E8%B1%A1%E7%B1%BB%E7%9A%84%E6%A6%82%E5%BF%B5%EF%BC%8C%E4%B8%BA%E4%BB%80%E4%B9%88%E8%A6%81%E6%9C%89%E6%8A%BD%E8%B1%A1%E7%B1%BB.md) [2.掌握抽象類的聲明格式](%E6%8E%8C%E6%8F%A1%E6%8A%BD%E8%B1%A1%E7%B1%BB%E7%9A%84%E5%A3%B0%E6%98%8E%E6%A0%BC%E5%BC%8F.md) [3.理解什么是接口，為什么要有接口](%E7%90%86%E8%A7%A3%E4%BB%80%E4%B9%88%E6%98%AF%E6%8E%A5%E5%8F%A3%EF%BC%8C%E4%B8%BA%E4%BB%80%E4%B9%88%E8%A6%81%E6%9C%89%E6%8E%A5%E5%8F%A3.md) [4.掌握接口的定義與實現](%E6%8E%8C%E6%8F%A1%E6%8E%A5%E5%8F%A3%E7%9A%84%E5%AE%9A%E4%B9%89%E4%B8%8E%E5%AE%9E%E7%8E%B0.md) [5.理解接口和抽象類的區別](%E7%90%86%E8%A7%A3%E6%8E%A5%E5%8F%A3%E5%92%8C%E6%8A%BD%E8%B1%A1%E7%B1%BB%E7%9A%84%E5%8C%BA%E5%88%AB.md) [6.實訓案例](6.%E5%AE%9E%E8%AE%AD%E6%A1%88%E4%BE%8B.md)