-
Notifications
You must be signed in to change notification settings - Fork 0
/
waterMark.html
98 lines (81 loc) · 2.96 KB
/
waterMark.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<script>
function careateWaterMark(options) {
if (!options.id) return
const canvasId = `#${options.id}`
let canvas = document.getElementById(canvasId)
canvas = canvas || document.createElement('canvas')
canvas.id = options.id
document.body.appendChild(canvas)
canvas.width = options.width || 300
canvas.height = options.height || 150
canvas.style.display = 'none'
const ctx = canvas.getContext('2d')
ctx.rotate((-20 * Math.PI) / 180)
ctx.font = options.font || '16px Microsoft JhengHei'
ctx.fillStyle = 'rgba(180, 180, 180, 0.7)'
ctx.textAlign = 'left'
ctx.textBaseline = 'middle'
ctx.fillText(options.text, -30, canvas.height / 1.4)
const containerId = `#${canvasId}-c-t-@`
let container = document.getElementById(containerId)
container = container || document.createElement('div')
container.id = containerId
const styleStr = `
width: 100%;
height: 100%;
position: fixed;
z-index: -1;
top: 0;
left: 0;
pointer-events: none;
background-image: url(${canvas.toDataURL('image/png')})
`
container.setAttribute('style', styleStr)
document.body.appendChild(container)
return {
canvasId,
containerId,
styleStr,
canvas,
container,
options
}
}
function WaterMark(options) {
let waterMark = careateWaterMark(options)
document.body[`${waterMark.canvasId}-observer`] = new MutationObserver(() => {
setTimeout(() => {
const instance = document.getElementById(waterMark.containerId)
const style = instance ? instance.getAttribute('style') : false
if (instance && style !== waterMark.styleStr) {
instance.setAttribute('style', waterMark.styleStr)
} else if (!instance) {
waterMark = careateWaterMark(options)
}
}, 1000)
})
document.body[`${waterMark.canvasId}-observer`].observe(document.body, {
childList: true,
attributes: true,
subtree: true
})
}
WaterMark({
font: '20px Microsoft JhengHei',
text: '阿测大魔王',
id: 'ace',
width: 500,
height: 200
})
</script>
</body>
</html>