Vue实现向PDF文件中添加二维码

pnpm add html2canvas
pnpm add qrcodejs2-fixes
pnpm add pdf-lib

import html2canvas from 'html2canvas'
import QRCode from 'qrcodejs2-fixes'
import { degrees, PDFDocument } from 'pdf-lib'

import html2canvas from 'html2canvas'
import QRCode from 'qrcodejs2-fixes'
import { degrees, PDFDocument } from 'pdf-lib'
 
export default function ({ pdfBlob, qrcodeUrl = 'https://www.baidu.com/' }) {
  if(!pdfBlob) return
  pdfBlob.arrayBuffer().then(async buffer => {
    const pdfDoc = await PDFDocument.load(buffer)
    const qrcodeDom = document.createElement('div')
    qrcodeDom.id = 'wft-qrcode'
    document.body.appendChild(qrcodeDom)
    new QRCode(document.getElementById('wft-qrcode'), {
      text: qrcodeUrl,
      width: '128',
      height: '128',
      colorDark: '#000000',
      colorLight: '#ffffff',
      correctLevel: QRCode.CorrectLevel.H,
    })
    html2canvas(document.getElementById('wft-qrcode')).then(canvas => {
      canvas.toBlob(qrcodeBlob => {
        qrcodeBlob.arrayBuffer().then(async qrcodeBuffer => {
          const image = await pdfDoc.embedPng(qrcodeBuffer)
          const dims = image.scale(0.6)
          const pages = pdfDoc.getPages()
          for (let i = 0; i < pages.length; i++) {
            let page = pages[i]
            const { width, height } = page.getSize()
            page.drawImage(image, {
              x: width - 100, // 距离右侧100
              y: height - 100, // 距离上侧100  就是右上角
              width: dims.width,
              height: dims.height,
              rotate: degrees(0)
            })
          }
          const pdfBytes = await pdfDoc.save()
          preView(pdfBytes)
          document.body.removeChild(qrcodeDom)
        })
      }, 'image/png')
    })
  })
}
 
// 打开新页签预览
function preView(stream, docTitle = '测试PDF') {
  const URL = window.URL || window.webkitURL;
  const href = URL.createObjectURL(new Blob([stream], { type: 'application/pdf;charset=utf-8' }))
  const wo = window.open(href)
  // 设置新打开的页签 document title
  let timer = setInterval(() => {
    if (wo.closed) {
      clearInterval(timer)
    } else {
      wo.document.title = docTitle
    }
  }, 500)
}

previewEmbedQrcodeToPdf({
  pdfBlob: file, // 你的文件流
  qrcodeUrl: 'xxxx' // 你的生成二维码的url链接
})

<template>
  <div class="main">
    <input id="fileInp" type="file">
  </div>
</template>
<script setup>
import { onMounted, onUnmounted } from 'vue'
import previewEmbedQrcodeToPdf from '../hooks/EmbedQrcodeToPdf'
let cusInp = null
onMounted(() => {
  cusInp = document.getElementById('fileInp')
  cusInp.addEventListener('input', inpHander)
})
onUnmounted(() => {
  cusInp.removeEventListener('input', inpHander)
})
function inpHander(event) {
  const file = event.target.files[0]
  if(!file) return
  previewEmbedQrcodeToPdf({
    pdfBlob: file
  })
}
</script>
<style scoped>
.main {
  width: 100%;
  height: 100%;
}
</style>