vue框架中实现多行水印，首页忽略水印

1.创建一个watermark.js

let watermark = {}

let setWatermark = (str1,str2,str3) => {
  let id = '1.23452384164.123412415'

  if (document.getElementById(id) !== null) {
    document.body.removeChild(document.getElementById(id))
  }
  //创建一个画布
  let can = document.createElement('canvas')
  //设置画布的长宽
  can.width = 460
  can.height = 240

  let cans = can.getContext('2d')
  //旋转角度
  cans.rotate(-15 * Math.PI / 180)
  cans.font = '15px Vedana'
  //设置填充绘画的颜色、渐变或者模式
  //cans.fillStyle = 'rgba(200, 200, 200, 0.40)'
  cans.fillStyle = '#666666'
  //设置文本内容的当前对齐方式
  cans.textAlign = 'center'
  //设置在绘制文本时使用的当前文本基线
  cans.textBaseline = 'Middle'
  //在画布上绘制填色的文本（输出的文本，开始绘制文本的x坐标位置，开始绘制文本的Y坐标位置）
  cans.fillText(str1, can.width / 2, can.height )
  cans.fillText(str2, can.width / 2, can.height+22 )
  cans.fillText(str3, can.width / 2, can.height+44 )

  let div = document.createElement('div')
  div.id = id
  div.style.pointerEvents = 'none'
  div.style.top = '40px'
  div.style.left = '0px'
  div.style.opacity = '0.15'
  div.style.position = 'fixed'
  div.style.zIndex = '100000'
  div.style.width = document.documentElement.clientWidth  + 'px'
  div.style.height = document.documentElement.clientHeight  + 'px'
  div.style.background = 'url(' + can.toDataURL('image/png') + ') left top repeat'
  document.body.appendChild(div)
  return id
}

//添加水印方法
watermark.set = (str1,str2,str3) => {
  let id = setWatermark(str1,str2,str3)
  setInterval(() => {
    if (document.getElementById(id) === null) {
      id = setWatermark(str1,str2,str3)
    }
  }, 2000)
  window.onresize = () => {
    setWatermark(str)
  }
}

//添加水印方法
watermark.set = (str1,str2,str3) => {
  let id = setWatermark(str1,str2,str3)
  if (document.getElementById(id) === null) {
    id = setWatermark(str1,str2,str3)
  }
}


//添加水印方法
watermark.remove = () => {
  let id = '1.23452384164.123412415'
   if (document.getElementById(id) !== null) {
     //document.body.removeChild(document.getElementById(id))
     const div = document.getElementById(id)
     div.style.display = 'none'
   }
}


export default watermark

cans.fillText设置了三个str，按个人需求设置,对方法中str1,str2,str3进行增减

2.在路由中设置

import Watermark from '@/utils/watermark.js'

router.afterEach((to) => {
    // finish progress bar
    localStorage.setItem("ms_time", "访问时间："+getTime());
    if (to.path === '/login') {
        Watermark.remove()
    }else{
        var ip = localStorage.getItem("ms_ip")
        if (ip === null) {
            this.http.get('/sys/staff/getIp', {}).then(res => {
                localStorage.setItem("ms_ip", "访问地址："+res);
            })
        }
        Watermark.set(localStorage.getItem("ms_username"),localStorage.getItem("ms_time"),localStorage.getItem("ms_ip"));
    }
    NProgress.done();
})

其中NProgress.done()；是个人项目中用的，可以忽略。主要还是对to.path是否为login进行不同的操作，具体操作视个人需求增减

效果：

水印效果图 

 

登陆页没有水印

 一键三连～鸣谢！