答： 如果你的水印是动态的，比如需要用到在登陆之后才能获取到的信息，可以在登陆接口成功的回调之后，调用一次该水印方法，然后将这些信息保存到localStorage中去，在main.js中获取，再调用一次该水印方法。这样，就可以实现动态的水印，且刷新不会消失。
参考： vue项目中添加水印
<!DOCTYPE html><html>
<head>
<meta charset="UTF-8">
<title>Document</title>
<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
<style>
.str {
font: normal bold 5px Arial
/*font-size: 5px*/
color: rgb(224, 226, 226,0.4)
position: absolute
padding-left: 16px
padding-top: 53px
display: none
}
.str2 {
font: normal bold 5px Arial
/* font-size: 5px*/
color: rgb(224, 226, 226,0.4)
position: absolute
padding-left: 66px
padding-top: 130px
display: none
}
</style>
</head>
<body>
<div>HOMEANGEL</div>
<div>HOMEANGEL</div>
<img src="https://dss2.bdstatic.com/70cFvnSh_Q1YnxGkpoWK1HF6hhy/it/u=3252521864,872614242&fm=26&gp=0.jpg" style="width:100pxheight:100px" />
<div id="picture" style="width:100%margin-left: 60px">
</div>
<script>
$(function () {
var img = ["https://dss2.bdstatic.com/70cFvnSh_Q1YnxGkpoWK1HF6hhy/it/u=3252521864,872614242&fm=26&gp=0.jpg"]
GetCanvas(img)
})
function AddCanvas(src, ById) {
var img = new Image()
img.src = src
img.onload = function () {
imgW = img.width
imgH = img.height
//准备canvas环境
var canvas = document.getElementById(ById)
canvas.width = img.width
canvas.height = img.height
var ctx = canvas.getContext("2d")
// 绘制图片
ctx.drawImage(img, 0, 0, img.width, img.height)
// 绘制水印
ctx.font = "20px bold Arial"
ctx.fillStyle = "rgb(224, 226, 226,0.6)"//这里是颜色
ctx.fillText("watermark watermark", 20, 60)
ctx.fillText("watermark watermark", 120, 160)
ctx.fillText("watermark watermark", 220, 220)
//ctx.fillText("HOMEANGEL", 90, 130)
canvas.style.width = "100px"
canvas.style.height = "100px"
}
}
function GetCanvas(Strhtml) {
if (Strhtml.length >0 &&Strhtml != "") {
var html = ""
for (var i = 0i <Strhtml.lengthi++) {
var str = "sample" + (i + 1)
html += ' <canvas id=' + str + ' name="test" src=' + Strhtml[i] + ' "></canvas>'
}
$("#picture").html(html)//这里图片添加到html，然后for，添加水印
}
for (var i = 0i <Strimg.lengthi++) {
var str = "sample" + (i + 1)
var src = Strhtml[i]
AddCanvas(src, str)//id没传递
}
}
</script>
</body>
