首先在assets目錄下新建watermark.js：
let watermark = {}
let setWatermark = (str) => {
let id = '1.23452384164.123412415'
if (document.getElementById(id) !== null) {
document.body.removeChild(document.getElementById(id))
}
let can = document.createElement('canvas')
can.width = 150
can.height = 120
let cans = can.getContext('2d')
cans.rotate(-20 * Math.PI / 180)
cans.font = '15px Vedana'
cans.fillStyle = 'rgba(0, 0, 0, 0.50)'
cans.textAlign = 'left'
cans.textBaseline = 'Middle'
cans.fillText(str, can.width / 20, can.height )
let div = document.createElement('div')
div.id = id
div.style.pointerEvents = 'none'
div.style.top = '3px'
div.style.left = '0px'
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
}
// 該方法只允許調(diào)用一次
watermark.set = (str) => {
let id = setWatermark(str)
setInterval(() => {
if (document.getElementById(id) === null) {
id = setWatermark(str)
}
}, 2000)
window.onresize = () => {
setWatermark(str)
}
}
export default watermark
然后在main.js引用
import watermark from '@/assets/watermark.js'
Vue.prototype.$watermark = watermark
最后在各個組件間使用，直接放帶mounted里
mounted()
{
this.$watermark.set("測試專用");
}
