Browser rearrangement, redraw differences and optimization means

1. Redraw: When the appearance of an element is changed (background color, font color, border color, etc.), the browser will redraw

2. Redrawn departure conditions

1. Add and delete visible DOM elements. 2. Page render initialization 5. Browser size change 6. OffsetTop, offsetLeft, OffsetWidth, offsetHeight, scrollTop, scrollLeft, scrollWidth, scrollHeight, clientTop, clientLeft, clientWidth, clientHeight, get ComputedStyle() (currentStyle in IE)

3. Optimization method

2. Do not set the DOM one by one. You can use className, csSText. Elements that manipulate DOM animations can be set to position: abolute,fixed to remove the element from the document flow 4. 5. Do not make queries when the layout information changes (this will force the render queue to refresh)