使用window.print()实现局部打印

<div ref="printQRCodeRef">
    <div class="qrcode-dialog-container">
        <img :src="locatorQRCodeDialogObj.qrcodeImgUrl" />
        <div ref="locatorQRCodeRef" style="display: none" align="center"></div>
     </div>
</div>

handlePrintQRCode() {
      let printHtml = this.$refs.printQRCodeRef.innerHTML; //获取指定打印区域
      let oldHtml = window.document.body.innerHTML;
      // 构建新网页(关键步骤,必须先构建新网页,在生成二维码,否则不能显示二维码)
      window.document.body.innerHTML = printHtml;
      // 调用打印功能
      window.print();
      window.document.body.innerHTML = oldHtml; //重新给页面内容赋值；
      return false;
}

handlePrintLocatorQRCode() {
      let printHtml = this.$refs.printQRCodeRef.innerHTML; //获取指定打印区域
      const iframe = document.getElementById('print-iframe');
      if (!iframe) {
        var el = document.getElementById('printcontent');
        iframe = document.createElement('IFRAME');
        var doc = null;
        iframe.setAttribute('id', 'print-iframe');
        iframe.setAttribute('style', 'position: absolute; width: 0px; height: 0px;left:-500px;top:-500px;');
        document.body.appendChild(iframe);
        doc = iframe.contentWindow.document;
        //这里可以自定义样式
        doc.write('<style media="print">@page {size: auto; margin: 0 mm;}</style>'); //解决出现页眉页脚和路径的问题
        doc.write('<div style="margin: 20px auto;">' + printHtml + '</div>');
        doc.close();
        iframe.contentWindow.focus();
      }
      setTimeout(function () {
        iframe.contentWindow.print();
      }, 50); //解决第一次样式不生效的问题
      if (navigator.userAgent.indexOf('MSIE') > 0) {
        document.body.removeChild(iframe);
      }
    }