PDF打印：html2canvas+jspdf

需求：将前端页面转为图片，再pdf打印

解决方案：html2canvas+jspdf

安装：

npm install html2canvas --save

npm install jspdf --save

创建js文件：

import html2Canvas from 'html2Canvas'
import jsPDF from 'jspdf'

export default{
  install (Vue, options) {
    Vue.prototype.getPdf = function (fileName) {
      var title = fileName;
      html2Canvas(document.querySelector('#exportTemplate'), {
        allowTaint: true
      }).then(function (canvas) {
        let contentWidth = canvas.width
        let contentHeight = canvas.height
        let pageHeight = contentWidth / 592.28 * 841.89
        let leftHeight = contentHeight
        let position = 0
        let imgWidth = 595.28
        let imgHeight = 592.28 / contentWidth * contentHeight
        let pageData = canvas.toDataURL('image/jpeg', 1.0)
        let PDF = new jsPDF('', 'pt', 'a4')
        if (leftHeight < pageHeight) {
          PDF.addImage(pageData, 'JPEG', 0, 0, imgWidth, imgHeight)
        } else {
          while (leftHeight > 0) {
            PDF.addImage(pageData, 'JPEG', 0, position, imgWidth, imgHeight)
            leftHeight -= pageHeight
            position -= 841.89
            if (leftHeight > 0) {
              PDF.addPage()
            }
          }
        }
        PDF.save(title + '.pdf')
      }
      )
    }
  }
}

使用：

在main.js中注册：

import printPdf from './components/common/printPdf/printPdf'
Vue.use(printPdf)

直接使用getPdf()

<bk-button @click="getPdf(fileName)">导出PDF</bk-button>

新需求补充：导出可滑动页面的所有数据

方案：

import html2Canvas from 'html2Canvas'
import jsPDF from 'jspdf'

export default{
  install (Vue, options) {
    Vue.prototype.getPdf = function (fileName) {
      var title = fileName;
      // 获取需要下载的ele
      var ele = document.querySelector('#exportTemplate')
      const originClientHeight = ele.clientHeight // 获取元素的原始可见高度 完成下载之后重新赋值
      // 将元素的高度设为可滑动区域的滚动高度
      ele.style.height = ele.scrollHeight + 'px'
      html2Canvas(ele, {
        allowTaint: true
      }).then(function (canvas) {
        ele.style.height = originClientHeight // 把元素高度重新设置为原来的高度，保证正常滑动
        let contentWidth = canvas.width
        let contentHeight = canvas.height
        let pageHeight = contentWidth / 592.28 * 841.89
        let leftHeight = contentHeight
        let position = 0
        let imgWidth = 595.28
        let imgHeight = 592.28 / contentWidth * contentHeight
        let pageData = canvas.toDataURL('image/jpeg', 1.0)
        let PDF = new jsPDF('', 'pt', 'a4')
        if (leftHeight < pageHeight) {
          PDF.addImage(pageData, 'JPEG', 0, 0, imgWidth, imgHeight)
        } else {
          while (leftHeight > 0) {
            PDF.addImage(pageData, 'JPEG', 0, position, imgWidth, imgHeight)
            leftHeight -= pageHeight
            position -= 841.89
            if (leftHeight > 0) {
              PDF.addPage()
            }
          }
        }
        PDF.save(title + '.pdf')
      }
      )
    }
  }
}

下载完成后，元素高度必须设置还原，否则原来的可滑动区域将不可再滑动