import html2canvas from 'html2canvas'
import jsPDF from 'jspdf'
import Vue from 'vue'
export const downloadPDF = (page, ne, isDownload) => {
  html2canvas(page, {
    allowTaint: true,
    taintTest: false,
    useCORS: true,
    // width:960,
    // height:5072,
    dpi: window.devicePixelRatio * 8, // 將分辨率提高到特定的DPI 提高四倍
    scale: 10 // 按比例增加分辨率
  }).then(function(canvas) {
    canvas2PDF(canvas, ne, isDownload)
  })
}
const canvas2PDF = (canvas, ne, isDownload) => {
  var contentWidth = canvas.width
  var contentHeight = canvas.height
  // 一頁pdf顯示html頁面生成的canvas高度;
  var pageHeight = (contentWidth / 592.28) * 841.89
  // 未生成pdf的html頁面高度
  var leftHeight = contentHeight
  // 頁面偏移
  var position = 0
  // a4紙的尺寸[595.28,841.89]，html頁面生成的canvas在pdf中圖片的寬高
  var imgWidth = 595.28
  var imgHeight = (592.28 / contentWidth) * contentHeight
  var pageData = canvas.toDataURL('image/jpeg', 1.0)
  var PDF = new jsPDF('', 'pt', 'a4')
  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();
      }
    }
  }
  console.log('PDF', PDF)
  if (isDownload) {
    PDF.save(ne + '.pdf') // 這里是導(dǎo)出的文件名
  } else {
    var pdfData = PDF.output('datauristring')
    Vue.prototype.$baseURL = pdfData
    // sessionStorage.setItem('base64URL',pdfData);
    console.log(1)
  }
}

      <div class="pdf">
        <div ref="pdf" class="page">你好</div>
    </div>
 
//引入
import { downloadPDF, canvas2PDF } from '../../utils/pdf' // 工具方法，導(dǎo)出操作
 
 
handleExport() {  
  var zhis = this
      var dsq = setTimeout(() => {
        downloadPDF(this.$refs.pdf, `CUKH Tax Invoice - ${this.form.invoiceNo}`, true)
 
      }, 100)
}

npm install vue-print-nb --save

//print.js 里的代碼
// 打印類屬性、方法定義
/* eslint-disable */
const Print =function(dom, options) {
    if (!(this instanceof Print)) return new Print(dom, options);
  
    this.options = this.extend({
      'noPrint': '.no-print'
    }, options);
  
    if ((typeof dom) === "string") {
      this.dom = document.querySelector(dom);
    } else {
      this.dom = dom;
    }
  
    this.init();
  };
  Print.prototype = {
  
    init: function () {
      var content = this.getStyle() + this.getHtml();
      this.writeIframe(content);
    },
    
    extend: function (obj, obj2) {
      for (var k in obj2) {
        obj[k] = obj2[k];
      }
      return obj;
    },
  
    getStyle: function () {
      var str = "",
        styles = document.querySelectorAll('style,link');
      for (var i = 0; i < styles.length; i++) {
        str += styles[i].outerHTML;
      }
      str += "<style>" + (this.options.noPrint ? this.options.noPrint : '.no-print') + "{display:none;}</style>";
  
      return str;
    },
  
    getHtml: function () {
      var inputs = document.querySelectorAll('input');
      var textareas = document.querySelectorAll('textarea');
      var selects = document.querySelectorAll('select');
  
      for (var k in inputs) {
        if (inputs[k].type == "checkbox" || inputs[k].type == "radio") {
          if (inputs[k].checked == true) {
            inputs[k].setAttribute('checked', "checked")
          } else {
            inputs[k].removeAttribute('checked')
          }
        } else if (inputs[k].type == "text") {
          inputs[k].setAttribute('value', inputs[k].value)
        }
      }
  
      for (var k2 in textareas) {
        if (textareas[k2].type == 'textarea') {
          textareas[k2].innerHTML = textareas[k2].value
        }
      }
  
      for (var k3 in selects) {
        if (selects[k3].type == 'select-one') {
          var child = selects[k3].children;
          for (var i in child) {
            if (child[i].tagName == 'OPTION') {
              if (child[i].selected == true) {
                child[i].setAttribute('selected', "selected")
              } else {
                child[i].removeAttribute('selected')
              }
            }
          }
        }
      }
  
      return this.dom.outerHTML;
    },
  
    writeIframe: function (content) {
      var w, doc, iframe = document.createElement('iframe'),
          f = document.body.appendChild(iframe);
      iframe.id = "myIframe";
      iframe.style = "position:absolute;width:0;height:0;top:-10px;left:-10px;";
      
      w = f.contentWindow || f.contentDocument;
      doc = f.contentDocument || f.contentWindow.document;
      doc.open();
      doc.write(content);
      doc.close();
      this.toPrint(w);
      
      setTimeout(function () {
        document.body.removeChild(iframe)
      }, 100)
    },
    
    toPrint: function (frameWindow) {
      try {
        setTimeout(function () {
          frameWindow.focus();
          try {
            if (!frameWindow.document.execCommand('print', false, null)) {
              frameWindow.print();
            }
          } catch (e) {
            frameWindow.print();
          }
          frameWindow.close();
        }, 10);
      } catch (err) {
        console.log('err', err);
      }
    }
  };
  
  const MyPlugin = {}
  MyPlugin.install = function (Vue, options) {
    Vue.prototype.$print = Print
  }
  
  export default MyPlugin

import Print from './plugs/print'
Vue.use(Print)

      <div class="pdf">
        <div ref="pdf" class="page">你好</div>
    </div>
 
    handleExport() {
 
      setTimeout(() => {
                this.$print(this.$refs.pdf)
          }, 100);
 
    },

@media print {
  @page {
        margin: 0 !important;
    }
   .pdf{
        position: fixed;
        top: -265px !important;
        left: -150px !important;
        transform: translate(-50%, -50%);
        transform: scale(0.7);
        box-shadow:none !important;
   }
 
  
  }

this.print( this.print(this.print(this.refs.print,{‘no-print':‘.do-not-print-me-xxx'})