在utils文件夹中创建 wartermark.ts 文件（位置看自己的组件放那，这都行），内容如下：
1 "use strict"; 2 3 const setWatermark = (str: any) => { 4 const id = "1.23452384164.123412416"; 5 6 if (document.getElementById(id) !== null) { 7 document.body.removeChild(document.getElementById(id) as any); 8 } 9 10 //创建一个画布 11 const can = document.createElement("canvas"); 12 //设置画布的长宽 13 can.width = 250; 14 can.height = 120; 15 16 const cans: any = can.getContext("2d"); 17 //旋转角度 18 cans.rotate((-15 * Math.PI) / 150); 19 cans.font = "18px Vedana"; 20 //设置填充绘画的颜色、渐变或者模式 21 cans.fillStyle = "rgba(200, 200, 200, 0.30)"; 22 //设置文本内容的当前对齐方式 23 cans.textAlign = "left"; 24 //设置在绘制文本时使用的当前文本基线 25 cans.textBaseline = "Middle"; 26 //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） 27 cans.fillText(str, can.width / 8, can.height / 2); 28 29 const div = document.createElement("div"); 30 div.id = id; 31 div.style.pointerEvents = "none"; 32 div.style.top = "35px"; 33 div.style.left = "0px"; 34 div.style.position = "fixed"; 35 div.style.zIndex = "100000"; 36 div.style.width = document.documentElement.clientWidth + "px"; 37 div.style.height = document.documentElement.clientHeight + "px"; 38 div.style.background = 39 "url(" + can.toDataURL("image/png") + ") left top repeat"; 40 document.body.appendChild(div); 41 return id; 42 }; 43 const watermark = { 44 // 该方法只允许调用一次 45 set: (str: any) => { 46 let id = setWatermark(str); 47 setInterval(() => { 48 if (document.getElementById(id) === null) { 49 id = setWatermark(str); 50 } 51 }, 500); 52 window.onresize = () => { 53 setWatermark(str); 54 }; 55 } 56 } 57 export default watermark;
2、在API.vue文件中引用 wartermark.ts
1 <script lang="ts"> 2 import './assets/styles/base.scss' 3 import { Component, Vue } from 'vue-property-decorator' 4 import { theme, getQueryString } from '@/utils/util' 5 import logoutUrl from '@/utils/api/logoutUrl' 6 7 import Watermark from '@/utils/main/wartermark'; 8 9 export default class App extends Vue { 10 mounted () { 11 Watermark.set("水印内容") 12 } 13 14 } 15 </script>