Do a scrollbar thinking

Use  offsetWidth  and  offsetHeight  Calculation  inner  The width and height of , Not because  margin  Negative values affect the calculation

Default  width: 100%;  Yes, it will be calculated automatically , But because   The outer layer can be changed , So it's still computationally safe

[x]scrollbar  The default scroll bar for , Modern browsers can be completely wiped out by style , It is no longer a key point to deal with

[] Calculation  scrollbar dom box-sizing  The various states of , Calculate internal  inner dom  The style you need to generate

[]inner  Whether to set the dead width and height , This can solve the internal problem  slot  When applied, there is no outer layer  width  perhaps  height  The time style is abnormal , however  scrollbar  How to synchronize the updated styles

[]scrollbar  After dynamically adding styles , How to synchronize , Is it ok to pass  ResizeListener  Handle

[]Inner  contain  padding box-sizing  How to deal with such styles