效果: 之前的效果图现在更好看了点
使用工具及依赖包：
主要：vue, vue-cli,vue-router, pdfjs-dist,
下载vue和vue-cli 创建项目和vue-router就不说了， 使用pdfjs-dis @2.0.943版本下次在换新版本看看
npm install --save pdfjs-dis@2.0.943更改文件：将App.vue 更改 :
HTML和CSS部分：
注意：css, html 部分更改添加请适当.
之前的定位问题已经优化 ,如果还出现了问题评论上提醒我.
<template>
<div class="pdf-stamp" onbeforecopy='return false' onselect='document.selection.empty()' ondragstart='return false' onselectstart ='return false' >
<div class="scroll-box" @scroll="onScroll">
<div class="scroll-warp">
<div class="seal-list">
<div class="title"> 印章 </div>
<div class="seal-img">
<div class="seal-img-content">
<div v-for="(item, index) of sealOfTheList" :key="index" class="seal-item">
<div class="img-name"> {{ item.name }} </div>
<div class="img-content">
<img class="img" :src="item.img"
@mousedown.stop="moveDown"
/>
</div>
</div>
</div>
</div>
</div>
<div class="content-box">
<div class="with-file">
<input type="file" class="file" id="file" ref="fielinput" @change="uploadFile" style="display: none;"/>
<label class="select-file" for="file">选择文件</label>
<span class="file-name"> {{ fileName }} </span>
<button class="save-down" @click.stop="saveDown">立即下载</button>
</div>
<div class="canvas-box-border">
<div class="canvas-content" ref="canvasBox">
<canvas ref="pdfCanvas" class="canvas-pdf"> </canvas>
</div>
</div>
<div class="foot-bar">
<button @click="clickPre">上一页</button>
<span>第 {{ pageNo }} / {{ pdfPageNumber }} 页</span>
<button @click="clickNext">下一页</button>
</div>
</div>
</div>
</div>
</div>
</template>
<style scoped>
.pdf-stamp {
width: 100vw;
height: 100vh;
background-color: white;
overflow: hidden;
position: relative;
z-index: 1;
}
.scroll-box {
width: 100vw;
height: 100vh;
overflow-x: hidden;
overflow-y: scroll;
position: relative;
}
.scroll-box::-webkit-scrollbar {
display: none;
}
.scroll-warp {
display: flex;
position: relative;
}
.seal-list {
height: 400px;
text-align: center;
border: 2px solid #d3cece;
background-color: #e7e7e7;
display: flex;
flex-direction: column;
margin: 50px 100px;
border-radius: 5px;
}
.title {
font-size: 20px;
margin: 0 10px;
font-weight: 600;
padding: 5px;
color: #7a7a7a;
border-bottom: 1px solid #d6d6d6;
}
.seal-img {
flex: 1;
overflow-x: hidden;
overflow-y: scroll;
}
.seal-img::-webkit-scrollbar {
display: none;
}
.seal-img-content {
padding: 0 10px;
}
.seal-item {
margin: 10px 0;
}
.img-name {
color: #b6b6b6;
font-weight: 600;
padding: 10px;
background-color: #fffdf9;
border-radius: 5px;
}
.img-content {
height: 100px;
display: flex;
justify-content: center;
align-items: center;
}
.img-content .img {
width: 100px;
}
.content-box {
text-align: center;
position: relative;
margin: 50px;
background-color: #f3efe6;
padding: 10px 25px;
border-radius: 5px;
}
.with-file {
display: flex;
align-items: center;
justify-content: space-between;
padding-bottom: 10px;
}
.select-file {
display: block;
padding: 10px 50px;
background-color: #e9d2ff;
color: #000;
border-radius: 5px;
}
.save-down {
padding: 10px 50px;
border-style: none;
display: block;
background-color: #e9d2ff;
border-radius: 5px;
}
.file-name {
color: #919191;
font-size: 18px;
font-weight: 600;
}
.canvas-box-border {
border: 4px double black;
}
.canvas-content {
width: 500px;
height: 700px;
position: relative;
}
.canvas-pdf {
width: 100%;
height: 100%;
}
.foot-bar {
position: relative;
padding: 10px;
display: flex;
justify-content: space-around;
align-items: center;
}
.foot-bar button {
border-style: none;
background-color: #efc9aa;
display: block;
padding: 10px 50px;
border-radius: 5px;
}
.foot-bar span {
color: #186666;
}
</style>注意：
不要试图更改class 为 with-file内的元素属性行内属性 肯能会js导致获取不到DOM效果失效
javaScript部分：
提示：有注释哪里的东西可以自由配置选项 不要更改其他地方的哦!
注意： 大多地方都写了注释说明了就不多说了
<script>
import pdfJS from "pdfjs-dist";
import "pdfjs-dist/build/pdf.worker.entry";
export default {
name: 'PdfStamp',
data() {
return {
pageNo: 0,
pdfPageNumber: 0,
renderingPage: false,
pdfData: null, // PDF的base64
sealDomList: [], //储存印章dom
scrollTop: 0, //scrollTop
once: false, //执行一次获取总之
/**
* option 设置项
*/
downFileText: "pdf_down_file", //下载文件名
fileStamp: true, //是否需要给文件盖章 才可下载
zIndex: 100, //给一个z-index 防止被其他元素遮盖导致立马触发mousedown 或者 mouseleave 删除元素
sealOfTheList: [
{ name: "携程旅行", img: "https://webresource.c-ctrip.com/ares2/nfes/pc-home/1.0.65/default/image/logo.png" },
{ name: "虎牙直播", img: "https://a.msstatic.com/huya/main3/static/img/logo.png" },
{ name: "厦门VG", img: "https://livewebbs2.msstatic.com/avatar_1_d52819f40bc198fbd1098b30dc1edacf.png" },
{ name: "画压印", img: "http://shopxmhs.oss-cn-beijing.aliyuncs.com/3e6ae202206221409453342.png" },
{ name: "招聘", img: "http://shopxmhs.oss-cn-beijing.aliyuncs.com/1daa8202206221409468728.png" },
{ name: "诚邀", img: "http://shopxmhs.oss-cn-beijing.aliyuncs.com/2c0ba202206221409472433.png" },
{ name: "广州TTG", img: "https://livewebbs2.msstatic.com/avatar_1_bf8ba03e1f78144d84f3538672ca282b.png" },
{ name: "成都AG超玩会", img: "https://esports-cdn.namitiyu.com/kog/team/FpDfD5z0hFN3N2gMpQHWx38qwmeF" },
],
scale: 3, // 缩放值
maxseal: 3, //最大seal数量
fileName: "尚未选择文件", //初始文件名
};
},
methods: {
/**
* 环境函数回调*******
*/
/**
* outMax()
* max: 设置的最大值 newVale 触发执行的值(max+1)
* 对应maxseal配置项
*/
outMax(max, /*newVal*/) {
console.log(`超出最大数量:${max}`);
},
/**
* notSelectFile 尚未选择文件回调
* 无参数
*/
notSelectFile() {
console.log('请选择文件');
},
/**
* notStamp 尚未选择文件回调
* 无参数
* 对应fileStamp配置项
*/
notStamp() {
console.log('请给文件盖章');
},
/**
* 展示file
*/
uploadFile() {
this.once = false;
let fileInput = this.$refs.fielinput;
let fileData = fileInput.files[0];
this.fileName = fileData.name;
let reader = new FileReader(); //文件读取
reader.readAsDataURL(fileData); //得到读取的文件
reader.onload = () => { //文件加载
let data = atob(
reader.result.substring(reader.result.indexOf(",") + 1) //取找到 ',' 符号后一个索引开始的所有数据 就是文件base64数据
/** reader = data:application/pdf;base64,(JVBERi0xLj... = data) data文件base64数据
atob() 函数源码:
globalScope.atob = function (input) {
return Buffer.from(input, 'base64').toString('binary'); 'binary' 转换'utf8'编码格式: 返回字符串
}
*/
);
this.loadPdfData(data);
};
},
loadPdfData(data) {
// 引入pdf.js的字体
let CMAP_URL = "https://unpkg.com/pdfjs-dist@2.0.943/cmaps/";
//读取base64的pdf流文件 返回pdf实例对象
this.pdfData = pdfJS.getDocument({
data: data, // PDF base64编码
cMapUrl: CMAP_URL,
cMapPacked: true,
});
this.renderPage(1);
},
// 根据页码渲染相应的PDF
renderPage(num, callback) { //num传入页 返回对应页的pdf数据
this.renderingPage = true;
this.pdfData.promise.then((pdf) => {
if (!this.once) {
this.once = true;
this.pdfPageNumber = pdf.numPages; //pdf.numPages 文件总页数
}
pdf.getPage(num).then((page) => {
// 获取DOM中为预览PDF准备好的canvasDOM对象 绘制内容
let canvas = this.$refs.pdfCanvas;
let viewport = page.getViewport(this.scale); //获取窗口属性
canvas.height = viewport.height;
canvas.width = viewport.width;
let ctx = canvas.getContext("2d");
let renderContext = {
canvasContext: ctx, //将对应ctx赋给renderContext.canvasContext 调用page.render(renderContext) 后内部 对应ctx.fillText() 绘制内容
viewport: viewport,
};
page.render(renderContext).then(() => { //渲染当前页内容
if (typeof(callback) === 'function') {
callback(ctx);
}
this.renderingPage = false;
this.pageNo = num; //获取当页内容
});
});
});
},
//上一页
clickPre() {
if (this.pdfPageNumber - 1 >= 1) {
this.renderPage(this.pageNo - 1);
}
},
//下一页
clickNext() {
if (this.pageNo + 1 <= this.pdfPageNumber) {
this.renderPage(this.pageNo + 1);
}
},
/**
* 创建seal dom
*/
//按下
moveDown(event) {
let _this = this;
let targetImg = event.srcElement; //触发的img
let yDistance = (targetImg.offsetHeight/2);
let xDistance = (targetImg.offsetWidth/2);
let sealDomList = this.sealDomList;
let addIndex = sealDomList.length;
//创建img
let img = targetImg.cloneNode(true);
img.tabIndex = addIndex;
img.style.position = 'absolute';
img.style.zIndex = this.zIndex;
img.style.width = targetImg.offsetWidth + 'px';
img.style.height = targetImg.offsetHeight + 'px';
img.style.backgroundPosition = 'center';
img.style.backgroundRepeat = 'no-repeat';
img.style.backgroundSize = '100%';
img.style.backgroundSize = '100%';
let xy = this.getCanvasBoxXY();
let canLeft = xy[0];
let canTop = xy[1];
_this.moveNode(img, (event.x - xDistance - canLeft), (event.y - yDistance - canTop + _this.scrollTop));
//移动
document.onmousemove = function(event) {
_this.moveNode(img, (event.x - xDistance - canLeft), (event.y - yDistance - canTop + _this.scrollTop));
}
//放下)
document.onmouseup = function () {
document.onmousemove = null;
document.onmouseup = null;
Promise.resolve(
_this.clearDOM(img, _this.$refs.canvasBox)
).then(res => {
if(!res) {
img.addEventListener( 'mousedown', _this.down, true);
img.addEventListener( 'mouseup', _this.up, true);
img.addEventListener( 'mouseleave', _this.leave, true);
}
})
}
//插入元素
this.$refs.canvasBox.appendChild(img);
_this.sealDomList.push(img); //储存seal dom
},
/*
canvasBox面向内部成员 view 定位 x, y
返回: 数组[x, y]
*/
getCanvasBoxXY() {
let canvasBox = this.$refs.canvasBox; //iamge放置定位盒子
let canLeft = this.getDomLeft(canvasBox, "offsetLeft");
let canTop = this.getDomLeft(canvasBox, "offsetTop");
return [canLeft, canTop];
},
//按下
down(e) { //拖拽 和 是否创建印章
let _this = this;
let ev = e.srcElement;
ev.style.zIndex = this.zIndex + 1; //我们希望拖拽印章的时候, 不会因为其他成员遮盖影响
let yDistance = (ev.offsetHeight/2);
let xDistance = (ev.offsetWidth/2);
let xy = this.getCanvasBoxXY();
let canLeft = xy[0];
let canTop = xy[1];
_this.moveNode(ev, (e.x - xDistance - canLeft), (e.y - yDistance - canTop + _this.scrollTop));
ev.onmousemove = function (event) {
_this.moveNode(ev, (event.x - xDistance - canLeft), (event.y - yDistance - canTop + _this.scrollTop));
}
},
//放下
up(event) { //停止拖拽且是否删除印章
let target = event.srcElement;
target.style.zIndex = this.zIndex; //我们希望结束拖拽操作后 印章的时候回到初始层级;
target.onmousemove = null;
this.clearDOM(target, this.$refs.canvasBox);
},
//离开
leave(event) { //停止拖拽
event.srcElement.onmousemove = null;
},
//定位
moveNode(event, x, y) {
event.style.left = x + 'px';
event.style.top = y + 'px';
},
/**
* 是否出界需清除
* 返回: 布尔值 是否被删除
*/
clearDOM(node, box) {
//node dom
let target = node;
let tarTop = target.offsetTop;
let tarLeft = target.offsetLeft;
let tarBottom = tarTop + target.offsetHeight;
let tarRight= tarLeft + target.offsetWidth;
//box dom
let fileDom = box;
let height = fileDom.offsetHeight;
let width = fileDom.offsetWidth;
if (tarBottom < 0 || tarTop > height) {
this.removeSealChild(target);
return true;
}else if (tarRight < 0 || tarLeft > width) {
this.removeSealChild(target);
return true;
}
if (this.sealDomList.length > this.maxseal) { //最seal大数量
this.outMax(this.maxseal, this.sealDomList.length );
this.removeSealChild(node);
return true;
}
return false;
},
//移除元素
removeSealChild(node) {
this.$refs.canvasBox.removeChild(node);
this.sealDomList.splice(node.tabIndex, 1);
for (let i = 0; i < this.sealDomList.length; i++) { //重新排序tabIndex标识
this.sealDomList[i].tabIndex = i;
}
},
/**
* canvas下载
*/
saveDown() {
if (!this.pageNo) {
return this.notSelectFile();
}else if (!this.sealDomList.length && this.fileStamp) {
return this.notStamp();
}else{
this.drawImage(this.sealDomList);
}
},
//绘制图片
drawImage(imageList) {
let canvas = this.$refs.pdfCanvas;
let canvasBox = this.$refs.canvasBox;
let _this = this;
if (!this.fileStamp && !this.sealDomList.length) { //跳过印章绘制
_this.canvasFile();
return _this.backInitialState(_this.sealDomList);
}
function func(ctx) {
let ratioX = canvas.width / canvasBox.offsetWidth;
let ratioY = canvas.height / canvasBox.offsetHeight;
let count = 0; //当前进度
let totalCount = imageList.length; //总进度
for (let image of imageList) {
let imgLeft = image.offsetLeft;
let imgTop = image.offsetTop;
let x = imgLeft * ratioX;
let y = imgTop * ratioY;
let img = new Image(20, 10);
img.crossOrigin = 'anonymous';
img.onload = () => {
count++;
ctx.drawImage(img, x, y, image.offsetWidth*ratioX, image.offsetHeight*ratioY);
if (count === totalCount) {
_this.canvasFile();
_this.backInitialState(_this.sealDomList);
}
};
img.src = image.src;
}
}
this.renderPage(this.pageNo, func);
},
//canvas 文件数据 下载
canvasFile() {
let canvas = this.$refs.pdfCanvas;
let dataURL = canvas.toDataURL('image/png'); //canva文件数据
this.downLoad(dataURL);
},
//下载文件
downLoad(url) {
let note = document.createElement('a');
note.download = this.downFileText; // 设置下载的文件名，默认是'下载'
note.href = url;
document.body.appendChild(note);
note.click();
note.remove();
},
//下载成功 清空印章
backInitialState(domList) {
this.renderPage(this.pageNo);
let len = domList.length;
for (let i = 0; i < len; i++) {
this.removeSealChild(domList[0]);
}
},
/**
* scrollTop
*/
onScroll(event) {
let target = event.srcElement;
this.scrollTop = target.scrollTop;
},
/**
* 查找DOM 的 style属性
*/
getStyleVal(node, styleStr) {
let style;
// let parent = node.parentNode;
if (node === document) { //window.getComputedStyle方法 不可调用 document 我们不对他查询
style = null;
}else {
style = window.getComputedStyle(node)[styleStr];
}
return style;
},
/**
* 去除单位得到数值
*/
matchNum(str) {
const regexp = /\d+(\.\d+)?/g; //匹配数字
return Number((str+"").match(regexp)[0]) >>> 0;
},
/**
* getDom 递归检测DOM 确定定位多次赋值 得到总真实offsetLeft 和 offsetTop
* key: 可选 offsetLeft 和 offsetTop
*/
getDomLeft(node) {
let _this = this;
let valueXY = [0, 0]; //储存值
let parent = node.parentNode;
let uncertain = ["static", "initial", "revert" , "unset" ]; //定位被确定
function dg(node, parent) {
/**
* //是否需要scrollXY (注销注释将不调用this.onScroll)
* valueXY[0] -= parent.scrollLeft; //scrollLeft
* valueXY[1] -= parent.scrollTop; //scrollTop
*/
if (!~uncertain.indexOf(_this.getStyleVal(parent, "position"))) {
valueXY[0] += node.offsetLeft + _this.matchNum(_this.getStyleVal(parent, "borderLeft"));
valueXY[1] += node.offsetTop + _this.matchNum(_this.getStyleVal(parent, "borderTop"));
return dg(parent, parent.parentNode); //多次上级访问找找到父节确定定位的元素 做 坐标 位置重新规划为定位后的元素 进行下次访问再取坐标
}else {
let grandParentNode = parent.parentNode
if (grandParentNode !== document) {
return dg(node, parent.parentNode); //如果没找到一直上级查找 知道抵达父级为 document查询结束
}else { //到达documen时候立即停止
valueXY[0] += node.offsetLeft;
valueXY[1] += node.offsetTop;
return valueXY;
}
}
}
return dg(node, parent);
}
}
}
</script>注意这几个印章路径可能存在跨域， 更换图片印章路径更改sealOfTheList数据对应路径即可。
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