使el-dialog实现弹窗拖拽

1.创建directive文件夹，里面创建directive.js文件

import Vue from 'vue';Vue.directive('dialogDrag', {bind(el, binding, vnode, oldVnode) {const dialogHeaderEl = el.querySelector('.el-dialog__header');// const dialogHeaderEl = el.querySelector('.el-dialog__footer');const dragDom = el.querySelector('.el-dialog');//dialogHeaderEl.style.cursor = 'move';dialogHeaderEl.style.cssText += ';cursor:move;'dragDom.style.cssText += ''// 获取原有属性 ie dom元素.currentStyle 火狐谷歌 window.getComputedStyle(dom元素, null);const sty = (function () {if (window.document.currentStyle) {return (dom, attr) => dom.currentStyle[attr];} else {return (dom, attr) => getComputedStyle(dom, false)[attr];}})()dialogHeaderEl.onmousedown = (e) => {// 鼠标按下，计算当前元素距离可视区的距离const disX = e.clientX - dialogHeaderEl.offsetLeft;const disY = e.clientY - dialogHeaderEl.offsetTop;const screenWidth = document.body.clientWidth; // body当前宽度const screenHeight = document.documentElement.clientHeight; // 可见区域高度(应为body高度，可某些环境下无法获取)const dragDomWidth = dragDom.offsetWidth; // 对话框宽度const dragDomheight = dragDom.offsetHeight; // 对话框高度const minDragDomLeft = dragDom.offsetLeft + dragDomWidth;const maxDragDomLeft = screenWidth - dragDom.offsetLeft;const minDragDomTop = dragDom.offsetTop;const maxDragDomTop = screenHeight - dragDom.offsetTop;// 获取到的值带px 正则匹配替换let styL = sty(dragDom, 'left');let styT = sty(dragDom, 'top');// 注意在ie中 第一次获取到的值为组件自带50% 移动之后赋值为pxif (styL.includes('%')) {styL = +document.body.clientWidth * (+styL.replace(/\%/g, '') / 100);styT = +document.body.clientHeight * (+styT.replace(/\%/g, '') / 100);} else {styL = +styL.replace(/\px/g, '');styT = +styT.replace(/\px/g, '');};document.onmousemove = function (e) {// 通过事件委托，计算移动的距离let left = e.clientX - disX;let top = e.clientY - disY;// 边界处理if (-(left) > minDragDomLeft) {left = -(minDragDomLeft);} else if (left > maxDragDomLeft) {left = maxDragDomLeft;}if (-(top) > minDragDomTop) {top = -(minDragDomTop);} else if (top > maxDragDomTop) {top = maxDragDomTop;}// 移动当前元素dragDom.style.cssText += `;left:${left + styL}px;top:${top + styT}px;`;};document.onmouseup = function (e) {document.onmousemove = null;document.onmouseup = null;};}}
})