1. 构造函数
2. AnimationEvent
3. 属性
4. animationName
5. bubbles
6. cancelable
7. composed
8. currentTarget
9. defaultPrevented
10. elapsedTime
11. eventPhase
12. hashCode
13. isTrusted
14. matchingTarget
15. path
16. runtimeType
17. target
18. timeStamp
19. type
20. 方法
21. composedPath
22. noSuchMethod
23. preventDefault
24. stopImmediatePropagation
25. stopPropagation
26. toString
27. 运算符
28. 运算符 ==