1.在utils里创建elTable.js

import { Table } from 'element-ui';
import { getCell, getColumnByCell } from 'element-ui/packages/table/src/util';
import { getStyle, hasClass } from 'element-ui/src/utils/dom';
Object.assign(Table.components.TableBody.methods, {handleCellMouseEnter(event, row) {const { table } = this;const cell = getCell(event);if (cell) {const column = getColumnByCell(table, cell);table.hoverState = { cell, column, row };const { hoverState } = table;table.$emit('cell-mouse-enter', hoverState.row, hoverState.column, hoverState.cell, event);}// 判断是否text-overflow, 如果是就显示tooltipconst cellChild = event.target.querySelector('.cell');if (!(hasClass(cellChild, 'el-tooltip') && cellChild.childNodes.length)) {return;}// use range width instead of scrollWidth to determine whether the text is overflowing// to address a potential FireFox bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1074543#c3const range = document.createRange();range.setStart(cellChild, 0);range.setEnd(cellChild, cellChild.childNodes.length);const rangeWidth = range.getBoundingClientRect().width;const padding = (parseInt(getStyle(cellChild, 'paddingLeft'), 10) || 0) + (parseInt(getStyle(cellChild, 'paddingRight'), 10) || 0);if ((rangeWidth + padding > cellChild.offsetWidth || cellChild.scrollWidth > cellChild.offsetWidth) && this.$refs.tooltip) {const { tooltip } = this.$refs;const { tooltipEnterable } = this.table;const showTooltip = () => {this.tooltipContent = cell.innerText || cell.textContent;tooltip.referenceElm = cell;if (tooltip.$refs.popper) {tooltip.$refs.popper.style.display = 'none';}tooltip.doDestroy();tooltip.setExpectedState(true);this.activateTooltip(tooltip);};if (tooltipEnterable && tooltip.showPopper) {clearTimeout(tooltip.timeoutEnter);tooltip.timeoutEnter = setTimeout(() => {if (!tooltip.expectedState) {tooltip.handleClosePopper();showTooltip();}tooltip.timeoutEnter = null;}, 100);return;}showTooltip();}},handleCellMouseLeave(event) {const { tooltip } = this.$refs;if (tooltip) {tooltip.setExpectedState(false);const { tooltipEnterable } = this.table;if (tooltipEnterable) {clearTimeout(tooltip.timeoutLeave);tooltip.timeoutLeave = setTimeout(() => {if (!tooltip.expectedState) {tooltip.handleClosePopper();}tooltip.timeoutLeave = null;}, 100);} else {tooltip.handleClosePopper();}}const cell = getCell(event);if (!cell) return;const oldHoverState = this.table.hoverState || {};this.table.$emit('cell-mouse-leave', oldHoverState.row, oldHoverState.column, oldHoverState.cell, event);}
});/*** @description 扩展el-table，实现当showOverflowTooltip时，鼠标可移入tooltip功能* @prop {Boolean} tooltipEnterable 仅在列属性showOverflowTooltip为true时生效，鼠标是否可进入到 tooltip 中，默认为true*/
const ElTable = {extends: Table,props: {tooltipEnterable: {type: Boolean,default: true}}
};
export default Vue => {Vue.component('ElTable', ElTable);
};

2.在main.js中引入 并绑在vue上

import ElTable from '@/utils/elTable';

Vue.use(ElTable);