The vue project realizes drawing a watermark in a certain area

'use strict'
 
const watermark = {}
 
/**
 *
 * @param {the content of the watermark to be set} str
 * @param {Container where watermark needs to be set} container
 */
const setWatermark = (str, container) => {
  const id = '1.23452384164.123412415'
 
  if (container === undefined) {
    return
  }
 
  // Check if there is one on the page, if so delete it if (document.getElementById(id) !== null) {
    const childelement = document.getElementById(id)
    childelement.parentNode.removeChild(childelement)
  }
 
  var containerWidth = container.offsetWidth // Get the width of the parent container var containerHeight = container.offsetHeight // Get the height of the parent container container.style.position = 'relative' // Set the layout to relative layout // Create a canvas element (make a background image first)
  const can = document.createElement('canvas')
  can.width = 390 // Set the width of each block can.height = 200 // Height const cans = can.getContext('2d') // Get the canvas cans.rotate(-20 * Math.PI / 180) // Rotate counterclockwise π/9
  cans.font = '20px Vedana' // Set the font cans.fillStyle = 'rgba(200, 200, 200, 0.20)' // Set the font color cans.textAlign = 'left' // Text alignment cans.textBaseline = 'Middle' // Text baseline cans.fillText(str, 0, 4 * can.height / 5) // Draw text // Create a div element const div = document.createElement('div')
  div.id = id // Set id
  div.style.pointerEvents = 'none' // Cancel all events div.style.top = '0px'
  div.style.left = '0px'
  div.style.position = 'absolute'
  div.style.zIndex = '100000'
  div.style.width = containerWidth + 'px'
  div.style.height = containerHeight + 'px'
  div.style.background = 'url(' + can.toDataURL('image/png') + ') left top repeat'
  container.appendChild(div) // Append to page return id
}
 
// This method can only be called once watermark.set = (str, container) => {
  let id = setWatermark(str, container)
  setInterval(() => {
    if (document.getElementById(id) === null) {
      id = setWatermark(str, container)
    }
  }, 500)
  // Listen for changes in page size window.onresize = () => {
    setWatermark(str, container)
  }
}
 
export default watermark

import Watermark from '@/external/watermark'

<div ref="directrecordwp" class="wrapper">

// Set the page watermark Watermark.set('College Party and Government Cloud Record Management Platform' + this.name, this.$refs.directrecordwp)