页面动态添加水印，来自：http://www.cnblogs.com/GongQi/p/4074609.html?utm_source=tuicool&utm_medium=referral
<HTML>
<HEAD>
<TITLE> 水印 </TITLE>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</HEAD>
<script type="text/javascript">
//创建水印div---start
var mask_div = document.createElement('div');
mask_div.id = 'mask_div1';
mask_div.appendChild(document.createTextNode("test"));
mask_div.style.position = "absolute";
mask_div.style.left = '20px';
mask_div.style.top = '20px';
mask_div.style.overflow = "hidden";
mask_div.style.zIndex = "9999";
mask_div.style.opacity = 0.3;
document.body.appendChild(mask_div);
//创建水印div---end
//调用创建水印的方法---start
function watermark(settings) {
//默认设置
var defaultSettings = {
watermark_getid:"id",
watermark_txt : "text",
watermark_x : 20,//水印起始位置x轴坐标
watermark_y : 20,//水印起始位置Y轴坐标
watermark_rows : 30,//水印行数
watermark_cols : 30,//水印列数
watermark_x_space : 50,//水印x轴间隔
watermark_y_space : 20,//水印y轴间隔
watermark_color : '#000000',//水印字体颜色
watermark_alpha : 0.3,//水印透明度
watermark_fontsize : '18px',//水印字体大小
watermark_font : '微软雅黑',//水印字体
watermark_width : 100,//水印宽度
watermark_height : 80,//水印长度
watermark_angle : 15
//水印倾斜度数
};
//采用配置项替换默认值，作用类似jquery.extend
if (arguments.length === 1 && typeof arguments[0] === "object") {
var src = arguments[0] || {};
for (key in src) {
if (src[key] && defaultSettings[key]
&& src[key] === defaultSettings[key])
continue;
else if (src[key])
defaultSettings[key] = src[key];
}
}
var oTemp = document.createDocumentFragment();
//获取页面最大宽度
//var page_width = Math.max(document.body.scrollWidth,document.body.clientWidth);
//获取div的宽度，将其宽度赋值给水印
var width = document.getElementById(defaultSettings.watermark_getid).offsetWidth;
var page_width = Math.max(width,width);
//获取页面最大长度 .offsetHeight
//获取div的高度，将其高度赋值给水印
var height = document.getElementById(defaultSettings.watermark_getid).offsetHeight
//var page_height = Math.max(document.body.scrollHeight,document.body.clientHeight);
var page_height = Math.max(height,height);
//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
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)) {
defaultSettings.watermark_cols = parseInt((page_width
- defaultSettings.watermark_x + defaultSettings.watermark_x_space)
/ (defaultSettings.watermark_width + defaultSettings.watermark_x_space));
defaultSettings.watermark_x_space = parseInt((page_width
- defaultSettings.watermark_x - defaultSettings.watermark_width
* defaultSettings.watermark_cols)
/ (defaultSettings.watermark_cols - 1));
}
//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
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)) {
defaultSettings.watermark_rows = parseInt((defaultSettings.watermark_y_space
+ page_height - defaultSettings.watermark_y)
/ (defaultSettings.watermark_height + defaultSettings.watermark_y_space));
defaultSettings.watermark_y_space = parseInt(((page_height - defaultSettings.watermark_y) - defaultSettings.watermark_height
* defaultSettings.watermark_rows)
/ (defaultSettings.watermark_rows - 1));
}
var x;
var y;
for (var i = 0; i < defaultSettings.watermark_rows; i++) {
y = defaultSettings.watermark_y
+ (defaultSettings.watermark_y_space + defaultSettings.watermark_height)
* i;
for (var j = 0; j < defaultSettings.watermark_cols; j++) {
x = defaultSettings.watermark_x
+ (defaultSettings.watermark_width + defaultSettings.watermark_x_space)
* j;
var mask_div = document.createElement('div');
mask_div.id = 'mask_div' + i + j;
mask_div.appendChild(document
.createTextNode(defaultSettings.watermark_txt));
//设置水印div倾斜显示
mask_div.style.webkitTransform = "rotate(-"
+ defaultSettings.watermark_angle + "deg)";
mask_div.style.MozTransform = "rotate(-"
+ defaultSettings.watermark_angle + "deg)";
mask_div.style.msTransform = "rotate(-"
+ defaultSettings.watermark_angle + "deg)";
mask_div.style.OTransform = "rotate(-"
+ defaultSettings.watermark_angle + "deg)";
mask_div.style.transform = "rotate(-"
+ defaultSettings.watermark_angle + "deg)";
mask_div.style.visibility = "";
mask_div.style.position = "absolute";
mask_div.style.left = x + 'px';
mask_div.style.top = y + 'px';
mask_div.style.overflow = "hidden";
mask_div.style.zIndex = "9999";
//mask_div.style.border="solid #eee 1px";
mask_div.style.opacity = defaultSettings.watermark_alpha;
mask_div.style.fontSize = defaultSettings.watermark_fontsize;
mask_div.style.fontFamily = defaultSettings.watermark_font;
mask_div.style.color = defaultSettings.watermark_color;
mask_div.style.textAlign = "center";
mask_div.style.width = defaultSettings.watermark_width + 'px';
mask_div.style.height = defaultSettings.watermark_height + 'px';
mask_div.style.display = "block";
oTemp.appendChild(mask_div);
}
;
}
;
var divSt = document.getElementById(defaultSettings.watermark_getid);//得到需要处理水印的div
divSt.appendChild(oTemp);//将水印添加到，需要处理的div下面
}
//调用创建水印的方法---end
</script>
<BODY>
<button onclick="watermark({watermark_text : '测试水印',watermark_getid:'tableid' })"></button>
<div id="divId">
<table width="500px" height="500px" border="1px" id="tableid">
<tr>
<td>11</td>
<td>11</td>
<td>11</td>
<td>11</td>
</tr>
<tr>
<td>22</td>
<td>22</td>
<td>22</td>
<td>22</td>
</tr>
<tr>
<td>33</td>
<td>33</td>
<td>33</td>
<td>33</td>
</tr>
</table>
</div>
</BODY>
</HTML>
展示效果：
