发现有些事件有些游览器会冒泡有些不会，具体有哪些坑呢？
blur、focus、load、unload是不会冒泡的~
每个 event 都有一个event.bubbles属性，可以知道它可否冒泡。(ref：W3定义的Event Interface)
当然 W3 DOM Level 3 Events 的细则里已经附上这个表格了：
| Event Type | Bubbling phase |
|---|---|
| abort | ✗ |
| beforeinput | ✔ |
| blur | ✗ |
| click | ✔ |
| compositionstart | ✔ |
| compositionupdate | ✔ |
| compositionend | ✔ |
| dblclick | ✔ |
| error | ✗ |
| focus | ✗ |
| focusin | ✔ |
| focusout | ✔ |
| input | ✔ |
| keydown | ✔ |
| keyup | ✔ |
| load | ✗ |
| mousedown | ✔ |
| mouseenter | ✗ |
| mouseleave | ✗ |
| mousemove | ✔ |
| mouseout | ✔ |
| mouseover | ✔ |
| mouseup | ✔ |
| resize | ✗ |
| scroll | ✔ |
| select | ✔ |
| unload | ✗ |
| wheel | ✔ |
还附上了 Legacy Events（旧浏览器支持的非标准遗留事件）的 bubble 属性。
| Event Type | Bubbling phase |
|---|---|
| DOMActivate | ✔ |
| DOMAttrModified | ✔ |
| DOMCharacterDataModified | ✔ |
| DOMFocusIn | ✔ |
| DOMFocusOut | ✔ |
| DOMNodeInserted | ✔ |
| DOMNodeInsertedIntoDocument | ✗ |
| DOMNodeRemoved | ✔ |
| DOMNodeRemovedFromDocument | ✗ |
| DOMSubtreeModified | ✔ |
| keypress | ✔ |
H5 还定义了一些新事件：
- media相关事件，都不冒泡
-
drag相关事件
dragstart、drag、dragenter、dragexit、dragleave、dragover、drop、dragend均冒泡 -
History相关事件：
popstate，hashchange冒泡（从window开始……所以意义在哪里），pagetransition不冒泡
还有很多H5新事件，大多在草案阶段，就不一一翻开了。