HTML添加水印的方法
作者：互联网
之前有个项目做完给用户演示的时候，界面上加了水印效果，今天把具体实现的方法分享一下。
首先看下效果：
核心js代码（shuiyin.js）：
1 function watermark(settings) {
2 //默认设置
3 var defaultSettings = {
4 watermark_txt: "text",
5 watermark_x: 20, //水印起始位置x轴坐标
6 watermark_y: 20, //水印起始位置Y轴坐标
7 watermark_rows: 20, //水印行数
8 watermark_cols: 20, //水印列数
9 watermark_x_space: 100, //水印x轴间隔
10 watermark_y_space: 50, //水印y轴间隔
11 watermark_color: '#aaa', //水印字体颜色
12 watermark_alpha: 0.4, //水印透明度
13 watermark_fontsize: '15px', //水印字体大小
14 watermark_font: '微软雅黑', //水印字体
15 watermark_width: 210, //水印宽度
16 watermark_height: 80, //水印长度
17 watermark_angle: 20 //水印倾斜度数
18 };
19 if (arguments.length === 1 && typeof arguments[0] === "object") {
20 var src = arguments[0] || {};
21 for (key in src) {
22 if (src[key] && defaultSettings[key] && src[key] === defaultSettings[key]) continue;
23 else if (src[key]) defaultSettings[key] = src[key];
24 }
25 }
26 var oTemp = document.createDocumentFragment();
27 //获取页面最大宽度
28 var page_width = Math.max(document.body.scrollWidth, document.body.clientWidth);
29 var cutWidth = page_width * 0.0150;
30 var page_width = page_width - cutWidth;
31 //获取页面最大高度
32 var page_height = Math.max(document.body.scrollHeight, document.body.clientHeight) + 450;
33 page_height = Math.max(page_height, window.innerHeight - 30);
34 //如果将水印列数设置为0，或水印列数设置过大，超过页面最大宽度，则重新计算水印列数和水印x轴间隔
35 if (defaultSettings.watermark_cols == 0 || (parseInt(defaultSettings.watermark_x + defaultSettings.watermark_width * defaultSettings.watermark_cols + defaultSettings.watermark_x_space * (defaultSettings.watermark_cols - 1)) > page_width)) {
36 defaultSettings.watermark_cols = parseInt((page_width - defaultSettings.watermark_x + defaultSettings.watermark_x_space) / (defaultSettings.watermark_width + defaultSettings.watermark_x_space));
37 defaultSettings.watermark_x_space = parseInt((page_width - defaultSettings.watermark_x - defaultSettings.watermark_width * defaultSettings.watermark_cols) / (defaultSettings.watermark_cols - 1));
38 }
39 //如果将水印行数设置为0，或水印行数设置过大，超过页面最大长度，则重新计算水印行数和水印y轴间隔
40 if (defaultSettings.watermark_rows == 0 || (parseInt(defaultSettings.watermark_y + defaultSettings.watermark_height * defaultSettings.watermark_rows + defaultSettings.watermark_y_space * (defaultSettings.watermark_rows - 1)) > page_height)) {
41 defaultSettings.watermark_rows = parseInt((defaultSettings.watermark_y_space + page_height - defaultSettings.watermark_y) / (defaultSettings.watermark_height + defaultSettings.watermark_y_space));
42 defaultSettings.watermark_y_space = parseInt(((page_height - defaultSettings.watermark_y) - defaultSettings.watermark_height * defaultSettings.watermark_rows) / (defaultSettings.watermark_rows - 1));
43 }
44 var x;
45 var y;
46 for (var i = 0; i < defaultSettings.watermark_rows; i++) {
47 y = defaultSettings.watermark_y + (defaultSettings.watermark_y_space + defaultSettings.watermark_height) * i;
48 for (var j = 0; j < defaultSettings.watermark_cols; j++) {
49 x = defaultSettings.watermark_x + (defaultSettings.watermark_width + defaultSettings.watermark_x_space) * j;
50 var mask_div = document.createElement('div');
51 mask_div.id = 'mask_div' + i + j;
52 mask_div.className = 'mask_div';
53 mask_div.appendChild(document.createTextNode(defaultSettings.watermark_txt));
54 //设置水印div倾斜显示
55 mask_div.style.webkitTransform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
56 mask_div.style.MozTransform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
57 mask_div.style.msTransform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
58 mask_div.style.OTransform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
59 mask_div.style.transform = "rotate(-" + defaultSettings.watermark_angle + "deg)";
60 mask_div.style.visibility = "";
61 mask_div.style.position = "absolute";
62 mask_div.style.left = x + 'px';
63 mask_div.style.top = y + 'px';
64 mask_div.style.overflow = "hidden";
65 mask_div.style.zIndex = "9999";
66 //让水印不遮挡页面的点击事件
67 mask_div.style.pointerEvents = 'none';
68 mask_div.style.opacity = defaultSettings.watermark_alpha;
69 mask_div.style.fontSize = defaultSettings.watermark_fontsize;
70 mask_div.style.fontFamily = defaultSettings.watermark_font;
71 mask_div.style.color = defaultSettings.watermark_color;
72 mask_div.style.textAlign = "center";
73 mask_div.style.width = defaultSettings.watermark_width + 'px';
74 mask_div.style.height = defaultSettings.watermark_height + 'px';
75 mask_div.style.display = "block";
76 oTemp.appendChild(mask_div);
77 };
78 };
79 document.body.appendChild(oTemp);
80 }
81
82 function getNow() {
83 var d = new Date();
84 var year = d.getFullYear();
85 var month = change(d.getMonth() + 1);
86 var day = change(d.getDate());
87 var hour = change(d.getHours());
88 var minute = change(d.getMinutes());
89 var second = change(d.getSeconds());
90
91 function change(t) {
92 if (t < 10) {
93 return "0" + t;
94 } else {
95 return t;
96 }
97 }
98 var time = year + '年' + month + '月' + day + '日 ' + hour + '时' + minute + '分' + second + '秒';
99 return time;
100 }
调用方法：
在html中引入jquery.js，shuiyin.js，然后使用以下代码调用：
watermark({ "watermark_txt": "水印文字内容"});
本文最开始预览效果的调用方式如下（不包含html部分，html无要求）：
1 var now = getNow();
2 watermark({ "watermark_txt": "样稿" + now });
标签：watermark,mask,水印,HTML,var,div,添加,defaultSettings 来源： https://www.cnblogs.com/bosins/p/15094168.html