html转pdf

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1、安装组件

yarn add html2canvas
yarn add jspdf

2、 编写 htmlToPdf.js

import html2canvas from "html2canvas"

import JsPDF from "jspdf"

/**

 * @param ele要生成 pdf 的DOM元素(容器)

 * @param padfName     PDF文件生成后的文件名字

 * */

export default {

  install(Vue, options) {

    Vue.prototype.getPdfFromHtml = function(ele, pdfFileName) {

      let eleW = ele.offsetWidth// 获得该容器的宽

      //   let eleH = ele.offsetHeight // 获得该容器的高

      let eleH = ele.scrollHeight// 获得该容器的高

      let eleOffsetTop = ele.offsetTop// 获得该容器到文档顶部的距离

      let eleOffsetLeft = ele.offsetLeft// 获得该容器到文档最左的距离

      var canvas = document.createElement('canvas')

      var abs = 0

      let win_in = document.documentElement.clientWidth || document.body.clientWidth// 获得当前可视窗口的宽度(不包含滚动条)

      let win_out = window.innerWidth// 获得当前窗口的宽度(包含滚动条)

      if (win_out > win_in) {

        // abs = (win_o - win_i)/2;    // 获得滚动条长度的一半

        abs = (win_out - win_in) / 2// 获得滚动条宽度的一半

      }

      canvas.width = eleW * 2// 将画布宽&&高放大两倍

      canvas.height = eleH * 2

      var context = canvas.getContext('2d')

      context.scale(2, 2) // 增强图片清晰度

      context.translate(-eleOffsetLeft - abs, -eleOffsetTop)

      html2canvas(ele, {

        dpi: 300,

        useCORS: true//允许canvas画布内可以跨域请求外部链接图片, 允许跨域请求。

      }).then(canvas => {

        var contentWidth = canvas.width

        var contentHeight = canvas.height

        //一页pdf显示html页面生成的canvas高度;

        var pageHeight = (contentWidth / 592.28) * 841.89 // 这样写的目的在于保持宽高比例一致 pageHeight/canvas.width = a4纸高度/a4纸宽度// 宽度和canvas.width保持一致

        //未生成pdf的html页面高度

        var leftHeight = contentHeight

        //页面偏移

        var position = 0

        //a4纸的尺寸[595.28,841.89],单位像素,html页面生成的canvas在pdf中图片的宽高

        var imgWidth = 595.28

        var imgHeight = (595.28 / contentWidth) * contentHeight

        var pageData = canvas.toDataURL('image/jpeg', 1.0)

        var pdf = new JsPDF('', 'pt', 'a4')

        //有两个高度需要区分,一个是html页面的实际高度,和生成pdf的页面高度(841.89)

        //当内容未超过pdf一页显示的范围,无需分页

        if (leftHeight < pageHeight) {

          //在pdf.addImage(pageData, 'JPEG', 左,上,宽度,高度)设置在pdf中显示;

          pdf.addImage(pageData, 'JPEG', 5, 0, imgWidth, imgHeight)

          // pdf.addImage(pageData, 'JPEG', 20, 40, imgWidth, imgHeight);

        } else {

          // 分页

          while (leftHeight > 0) {

            pdf.addImage(pageData, 'JPEG', 5, position, imgWidth, imgHeight)

            leftHeight -= pageHeight

            position -= 841.89

            //避免添加空白页

            if (leftHeight > 0) {

              pdf.addPage()

            }

          }

        }

        pdf.save(pdfFileName + '.pdf')

      })

    }

  }

}

3、main.js

import htmlToPdf from "@/utils/htmlToPdf"
Vue.use(htmlToPdf)

4、组件应用

mounted(){
  this.downloadSprintTestReport();
},
methods: {
  downloadSprintTestReport(){
    this.getPdfFromHtml(document.querySelector('.repair-wrap'),'报告');
  },
}