复制代码

    复制代码

export function scrollIntoView(el, scrollParent) {	if(el.scrollIntoViewIfNeeded) {		el.scrollIntoViewIfNeeded(false) // alignToCenter=false	} else {		const diff = el.offsetTop - scrollParent.scrollTop		if(diff < 0 || diff > scrollParent.offsetHeight - el.offsetHeight) {			scrollParent = scrollParent || el.parentElement			scrollParent.scrollTop = el.offsetTop		}	}}export function applyRange(range) {	const selection = window.getSelection()	if(selection) { // 容错		selection.removeAllRanges()		selection.addRange(range)	}}export function getRange() {	const selection = window.getSelection()	if(selection && selection.rangeCount > 0) {		return selection.getRangeAt(0)	}}export function getAtAndIndex(text, ats) {	return ats.map((at) => {		return {			at,			index: text.lastIndexOf(at)		}	}).reduce((a, b) => {		return a.index > b.index ? a : b	})}export function getOffset(element, target) {	target = target || window	var offset = {			top: element.offsetTop,			left: element.offsetLeft		},		parent = element.offsetParent;	while(parent != null && parent != target) {		offset.left += parent.offsetLeft;		offset.top += parent.offsetTop;		parent = parent.offsetParent;	}	return offset;}export function closest(el, predicate) {	do		if(predicate(el)) return el;	while (el = el && el.parentNode);}// http://stackoverflow.com/questions/15157435/get-last-character-before-caret-position-in-javascript// 修复 "空格+表情+空格+@" range报错 应设(endContainer, 0)// stackoverflow上的这段代码有bugexport function getPrecedingRange() {	const r = getRange()	if(r) {		const range = r.cloneRange()		range.collapse(true)		range.setStart(range.endContainer, 0)		return range	}}复制代码