Vue implements zoom in, zoom out and drag function

import Vue from 'vue';
import bigPic from '../assets/images/bigChange.png';
// v-dialogDrag: pop-up window drag attribute Vue.directive('dialogDrag', {
  bind(el, binding, vnode, oldVnode) {
    //The minimum width and height of the bullet box let minWidth = 400; 
    let minHeight = 300; 
    //Initial non-full screen let isFullScreen = false; 
    //Current width and height let nowWidth = 0; 
    let nowHight = 0; 
    //Current top height let nowMarginTop = 0; 
    //Get the header of the pop-up box (this part can be double-clicked to full screen) 
    const dialogHeaderEl = el.querySelector('.el-dialog__header'); 
    //Pop-up window const dragDom = el.querySelector('.el-dialog'); 
    // Full screen button dialogHeaderEl.insertAdjacentHTML('beforeEnd', '<div class="bigbtn"><div class="changeBig"></div><div class="changeSmall"></div></div>'); 
    const bigBtn = el.querySelector('.bigbtn'); 
    const changeBig = el.querySelector('.changeBig'); 
    const changeSmall = el.querySelector('.changeSmall');
    //Add overflow auto to the pop-up window; otherwise the label in the box may exceed the dialog when it is reduced; 
    dragDom.style.overflow = "auto"; 
    //Clear the selected header text effect//dialogHeaderEl.onselectstart = new Function("return false"); 
    //Add a draggable cursor to the head 
    dialogHeaderEl.style.cursor = 'move'; 
    // Get the original attributes ie dom element.currentStyle firefox google window.getComputedStyle(dom element, null); 
    const sty = dragDom.currentStyle || window.getComputedStyle(dragDom, null); 
    let moveDown = (e) => {
      // Press the mouse to calculate the distance between the current element and the visible area const disX = e.clientX - dialogHeaderEl.offsetLeft; 
      const disY = e.clientY - dialogHeaderEl.offsetTop; 
      // Get the value with px regular expression to replace let styL, styT;
      // Note that in IE, the first value obtained is the component's own 50% and the value is assigned to px after moving 
      if (sty.left.includes('%')) {
        styL = +document.body.clientWidth * (+sty.left.replace(/\%/g, '') / 100); 
        styT = +document.body.clientHeight * (+sty.top.replace(/\%/g, '') / 100);
 
      } else { 
        styL = +sty.left.replace(/\px/g, '');
        styT = +sty.top.replace(/\px/g, '');
 
      };
 
      document.onmousemove = function (e) {
        // Calculate the moving distance through event delegation const l = e.clientX - disX;
        const t = e.clientY - disY; 
        // Move the current element dragDom.style.left = `${l + styL}px`;
        dragDom.style.top = `${t + styT}px`;
 
        //Pass the current position //binding.value({x:e.pageX,y:e.pageY})
 
      };
 
      document.onmouseup = function (e) { 
        document.onmousemove = null; 
        document.onmouseup = null;
 
      };
 
    }
 
    dialogHeaderEl.onmousedown = moveDown;
 
    //Double click the header to achieve full screen effect bigBtn.onclick = (e) => {
      if (isFullScreen == false) { 
        changeBig.style.display = 'none'; 
        changeSmall.style.display = 'block';
        nowHight = dragDom.clientHeight;
        nowWidth = dragDom.clientWidth; 
        nowMarginTop = dragDom.style.marginTop; 
        dragDom.style.left = 0; 
        dragDom.style.top = 0; 
        dragDom.style.height = "100VH";
        dragDom.style.width = "100VW"; 
        dragDom.style.marginTop = 0; 
        isFullScreen = true; 
        dialogHeaderEl.style.cursor = 'initial'; 
        dialogHeaderEl.onmousedown = null;
 
      } else {
 
        changeBig.style.display = 'block'; 
        changeSmall.style.display = 'none';
        dragDom.style.height = "auto"; 
        dragDom.style.width = nowWidth + 'px'; 
        dragDom.style.marginTop = nowMarginTop; 
        isFullScreen = false; 
        dialogHeaderEl.style.cursor = 'move';
 
        dialogHeaderEl.onmousedown = moveDown;
 
      }
 
    }
 
    dragDom.onmousemove = function (e) {
      // console.log(dialogHeaderEl,dragDom.querySelector('.el-dialog__body'), 123);
      let moveE = e;
 
      if (e.clientX > dragDom.offsetLeft + dragDom.clientWidth - 10 || dragDom.offsetLeft + 10 > e.clientX) {
         dragDom.style.cursor = 'w-resize';
      } else if (el.scrollTop + e.clientY > dragDom.offsetTop + dragDom.clientHeight - 10) { 
        dragDom.style.cursor = 's-resize'; 
      } else { 
        dragDom.style.cursor = 'default'; 
        dragDom.onmousedown = null;
 
      }
 
      dragDom.onmousedown = (e) => { 
        const clientX = e.clientX; 
        const clientY = e.clientY; 
        let elW = dragDom.clientWidth; 
        let elH = dragDom.clientHeight; 
        let EloffsetLeft = dragDom.offsetLeft;
        let EloffsetTop = dragDom.offsetTop;
        dragDom.style.userSelect = 'none';
        let ELscrollTop = el.scrollTop;
 
        //Judge whether the clicked position is the headif (clientX > EloffsetLeft && clientX < EloffsetLeft + elW && clientY > EloffsetTop && clientY < EloffsetTop + 100) {
 
          //If it is the header, no action will be taken here. The above is bound to dialogHeaderEl.onmousedown = moveDown;
 
        } else {
 
          document.onmousemove = function (e) {
            e.preventDefault(); // Disable default events when moving // Left mouse drag position if (clientX > EloffsetLeft && clientX < EloffsetLeft + 10) { 
              //Drag to the left if (clientX > e.clientX) { 
                dragDom.style.width = elW + (clientX - e.clientX) * 2 + 'px';
 
              }
 
              //Drag to the right if (clientX < e.clientX) { 
                if (dragDom.clientWidth < minWidth) {
                } else {
                dragDom.style.width = elW - (e.clientX - clientX) * 2 + 'px';
 
                }
 
              }
 
            }
 
            //Right mouse drag positionif (clientX > EloffsetLeft + elW - 10 && clientX < EloffsetLeft + elW) { 
              //Drag to the left if (clientX > e.clientX) {
                if (dragDom.clientWidth < minWidth) { 
                } else { 
                  dragDom.style.width = elW - (clientX - e.clientX) * 2 + 'px';
 
                }
 
              }
 
              //Drag to the right if (clientX < e.clientX) {
 
                dragDom.style.width = elW + (e.clientX - clientX) * 2 + 'px';
 
              }
 
            }
 
            //Bottom mouse drag positionif (ELscrollTop + clientY > EloffsetTop + elH - 20 && ELscrollTop + clientY < EloffsetTop + elH) {
 
              //Drag up if (clientY > e.clientY) {
                if (dragDom.clientHeight < minHeight) {
                } else {
 
                  dragDom.style.height = elH - (clientY - e.clientY) * 2 + 'px';
 
                }
 
              }
 
              //Drag down if (clientY < e.clientY) { 
                dragDom.style.height = elH + (e.clientY - clientY) * 2 + 'px';
 
              }
 
            }
 
          };
 
          //Stretching ends document.onmouseup = function (e) { 
            document.onmousemove = null; 
            document.onmouseup = null;
 
          };
 
        }
 
      }
 
    }
  }
})

import './utils/directives.js';

<el-dialog
     v-dialogDrag
      title="User Information"
      :visible.sync="dialogVisible"
      width="50%"
      :close-on-click-modal="false"
      :before-close="handleClose">
      <div>
        <el-table :data="phoneData" style="width: 100%">
          <el-table-column prop="fullName" label="Name" width="100"></el-table-column>
          <el-table-column prop="sex" label="Gender" width="80"></el-table-column>
          <el-table-column prop="idCard" label="ID number" min-width="120" show-overflow-tooltip></el-table-column>
          <el-table-column prop="mobile" label="Contact number" width="150"></el-table-column>
          <el-table-column prop="censusAreaName" label="Household Registration Division" min-width="120" show-overflow-tooltip></el-table-column>
          <el-table-column prop="censusAddr" label="Household Registration Address" min-width="100" show-overflow-tooltip></el-table-column>
          <el-table-column label="operation" width="120" fixed="right" align="center">
            <template slot-scope="{row}">
              <span @click="chooseInfor(row.id)" class="table-btn">Select</span>
            </template>
          </el-table-column>
        </el-table>
      </div>
</el-dialog>

.changeBig {
    width: 20px;
    height: 20px;
    background: url("../assets/images/bigChange.png") no-repeat center;
    background-size: 100% 100%;
    cursor: pointer;
    position: absolute;
    top: 14px;
    right: 60px;
}
.changeSmall {
    width: 20px;
    height: 20px;
    background: url("../assets/images/smallChange.png") no-repeat center;
    background-size: 100% 100%;
    cursor: pointer;
    position: absolute;
    top: 14px;
    right: 60px;
    display: none;
}