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@@ -0,0 +1,64 @@
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+let watermark = {}
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+let watermarkTimer = null
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+
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+let setWatermark = (str, date) => {
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+ let id = '1.23452384164.123412416'
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+
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+ if (document.getElementById(id) !== null) {
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+ document.body.removeChild(document.getElementById(id))
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+ }
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+
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+ //创建一个画布
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+ let can = document.createElement('canvas')
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+ //设置画布的长宽
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+ can.width = 500
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+ can.height = 350
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+
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+ let cans = can.getContext('2d')
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+ //旋转角度
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+ cans.rotate(-20 * Math.PI / 180)
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+ cans.font = '40px Vedana'
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+ //设置填充绘画的颜色、渐变或者模式
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+ cans.fillStyle = 'rgba(200, 200, 200, 0.40)'
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+ //设置文本内容的当前对齐方式
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+ cans.textAlign = 'left'
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+ //设置在绘制文本时使用的当前文本基线
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+ cans.textBaseline = 'Middle'
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+ //在画布上绘制填色的文本(输出的文本,开始绘制文本的X坐标位置,开始绘制文本的Y坐标位置)
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+ cans.fillText(str, can.width / 12, can.height / 2)
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+ cans.fillText(date, can.width / 12, can.height / 2)
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+ let div = document.createElement('div')
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+ div.id = id
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+ div.style.pointerEvents = 'none'
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+ div.style.top = '30px'
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+ div.style.left = '0px'
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+ div.style.position = 'absolute'
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+ div.style.zIndex = '100000'
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+ div.style.width = document.documentElement.clientWidth + 'px'
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+ div.style.height = document.documentElement.clientHeight + 'px'
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+ div.style.background = 'url(' + can.toDataURL('image/png') + ') left top repeat'
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+ // document.body.appendChild(div)
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+ div.style.opacity = '0.4' // 水印的透明度
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+ let show = document.getElementById("showWaterMark") // 控制水印显示的区域,设置id = show,表示在该范围内有水印
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+ if (!show) {
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+ clearInterval(watermarkTimer)
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+ return
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+ }
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+ show.appendChild(div)
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+ return id
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+}
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+
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+// 该方法只允许调用一次
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+watermark.set = (str, date) => {
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+ let id = setWatermark(str, date) // str,date代表的是两行水印。如果需好几个的话再追加。
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+ watermarkTimer = setInterval(() => {
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+ if (document.getElementById(id) === null) {
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+ id = setWatermark(str, date)
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+ }
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+ }, 500);
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+ window.onresize = () => {
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+ setWatermark(str, date)
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+ };
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+}
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+
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+export default watermark
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