前端实现页面水印

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我是靠谱客的博主追寻魔镜，这篇文章主要介绍前端实现页面水印，现在分享给大家，希望可以做个参考。

前端实现页面水印的思路,先将名称画到canvas上,再将canvas生成base64图片格式作为盒子的背景图追加到页面上,其中利用pointer-events: none属性实现点击穿透.

复制代码

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const watermark = {};
function setWatermark(str) {
const id = '1.23452384164.123412415';
if (document.getElementById(id) !== null) {
document.body.removeChild(document.getElementById(id));
}
const can = document.createElement('canvas');
can.width = 150;
can.height = 120;
const cans = can.getContext('2d');
cans.rotate(-20 * Math.PI / 180);
cans.font = '20px Vedana';
cans.fillStyle = 'rgba(200, 200, 200, 0.20)';
cans.textAlign = 'left';
cans.textBaseline = 'Middle';
cans.fillText(str, can.width / 3, can.height / 2);
const div = document.createElement('div');
div.id = id;
// 点击穿透
div.style.pointerEvents = 'none';
div.style.top = '70px';
div.style.left = '0px';
div.style.position = 'fixed';
div.style.zIndex = '2000';
div.style.width = document.documentElement.clientWidth - 100 + 'px';
div.style.height = document.documentElement.clientHeight - 100 + 'px';
div.style.background = 'url(' + can.toDataURL('image/png') + ') left top repeat';
document.body.appendChild(div);
return id;
};
// 该方法只允许调用一次
watermark.set = function (str) {
const id = setWatermark(str);
setInterval(() => {
if (document.getElementById(id) === null) {
id = setWatermark(str);
}
}, 500);
window.onresize = () => {
setWatermark(str);
};
};
export default watermark;