html2canvas转pdf

import html2canvas from 'html2canvas'
import jsPDF from 'jspdf'

html2canvas(document.body).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;
    //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]，html页面生成的canvas在pdf中图片的宽高
    var imgWidth = 595.28;
    var imgHeight = 592.28/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) {
        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;
            //避免添加空白页
            if(leftHeight > 0) {
                pdf.addPage();
            }
        }
    }

    pdf.save('content.pdf');
})

官网：https://github.com/niklasvh/html2canvas

　　　　dataURLtoFile() {

        var arr = this.dataUrl.split(','),

            bstr = atob(arr[1]),

            n = bstr.length,

            u8arr = new Uint8Array(n);

        while (n--) {

            u8arr[n] = bstr.charCodeAt(n);

        }

        return new Blob([u8arr], { type: 'file' });

    },

 

// 将base64转换为file
    dataURLtoFile() {
      var arr = this.dataUrl.split(','),
          bstr = atob(arr[1]),
          n = bstr.length,
          u8arr = new Uint8Array(n);
      while (n--) {
          u8arr[n] = bstr.charCodeAt(n);
      }
      return new Blob([u8arr], { type: 'file' });
    },
// 将file上传
    uploadFile() {
      const formData = new FormData()
      formData.append('file', this.dataURLtoFile())
      this.$http.post('/v1/upload/file', formData, {
        'Content-Type':'multipart/form-data'
      }).then(res => {
        console.log(res);
      })
    },