> For the complete documentation index, see [llms.txt](https://wilden-chen.gitbook.io/swift-design-patterns/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wilden-chen.gitbook.io/swift-design-patterns/decorator.md).

# 裝飾者模式 - Decorator

裝飾者模式可以動態的給指定的類別添加一些行為和職責，而不用對原使類別進行任何修改。當你需要使用子類別的時候，不妨考慮一下裝飾者模式，可以在原始類別上面封裝一層。

在 Swift，有兩種方式實現裝飾者模式：擴展 (Extension) 和委派 (Delegation)。


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