vue实现element-ui对话框可拖拽功能

import Vue from 'vue'; // v-dialogDrag: 弹窗拖拽属性Vue.directive('dialogDrag', {  bind(el, binding, vnode, oldVnode) {    const dialogHeaderEl = el.querySelector('.el-dialog__header');    const dragDom = el.querySelector('.el-dialog');    //dialogHeaderEl.style.cursor = 'move';    dialogHeaderEl.style.cssText += ';cursor:move;'    dragDom.style.cssText += ';top:0px;'     // 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;        const maxDragDomLeft = screenWidth - dragDom.offsetLeft - dragDomWidth;                const minDragDomTop = dragDom.offsetTop;        const maxDragDomTop = screenHeight - dragDom.offsetTop - dragDomheight;             // 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px      if(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;      };    }   }})

document.body.clientWidth //BODY对象宽度document.body.clientHeight //BODY对象高度document.documentElement.clientWidth //可见区域宽度document.documentElement.clientHeight //可见区域高度

// 引入Dialog可拖拽，注意文件所在目录。目前尚未发现引入的先后关系，若有再补充import './directives.js';

<el-dialog v-dialogDrag></el-dialog>