react批量下载pdf,并且打包zip

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import html2canvas from "html2canvas";
import jsPDF from "jspdf";
import JSZip from "jszip";
import FileSaver from "file-saver";
function downPdf () {
    let zipData = [];
    const element = document.getElementById("demo"); // 这个dom元素是要导出的pdf的div容器
    const w = element.offsetWidth; // 获得该容器的宽
    const h = element.offsetHeight; // 获得该容器的高
    const offsetTop = element.offsetTop; // 获得该容器到文档顶部的距离
    const offsetLeft = element.offsetLeft; // 获得该容器到文档最左的距离
    const canvas = document.createElement("canvas");
    let abs = 0;
    const win_i = document.body.clientWidth; // 获得当前可视窗口的宽度(不包含滚动条)
    const win_o = window.innerWidth; // 获得当前窗口的宽度(包含滚动条)
    if (win_o > win_i) {
      abs = (win_o - win_i) / 2; // 获得滚动条宽度的一半
    }
    canvas.width = w * 2; // 将画布宽&&高放大两倍
    canvas.height = h * 2;
    const context = canvas.getContext("2d");
    context.scale(2, 2);
    context.translate(-offsetLeft - abs, -offsetTop);
    // 这里默认横向没有滚动条的情况,因为offset.left(),有无滚动条的时候存在差值,因此translate的时候,要把这个差值去掉
    html2canvas(element, {
      allowTaint: true,
      scale: 2, // 提升画面质量,但是会增加文件大小
    }).then((canvas) => {
      const contentWidth = canvas.width;
      const contentHeight = canvas.height;
      // 一页pdf显示html页面生成的canvas高度
      const pageHeight = (contentWidth / 592.28) * 841.89;
      // 未生成pdf的html页面高度
      const leftHeight = contentHeight;
      // 页面偏移
      const 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
      const imgWidth = 595.28;
      const imgHeight = (592.28 / contentWidth) * contentHeight;

      const pageDate = canvas.toDataURL("image/jpeg", 1.0);

      const 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的页面的高度(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(pageDate, "JPEG", 0, position, imgWidth, imgHeight);
      } else {
        // 分页
        while (leftHeight > 0) {
          pdf.addImage(pageDate, "JPEG", 0, position, imgWidth, imgHeight);
          leftHeight -= pageHeight;
          position -= 841.89;
          // 避免添加空白页
          if (leftHeight > 0) {
            pdf.addPage();
          }
        }
      }

      zipData.push({
        PDF: pdf,
        name: `${code}.pdf`,
      });

      const zip = new JSZip();
      if (zipData.length === downList.length) {
        for (let i = 0; i < zipData.length; i++) {
          const { PDF, name } = zipData[i];
          zip.file(`${name}.pdf`, PDF.output("blob"));
        }

        zip.generateAsync({ type: "blob" }).then((content) => {
          FileSaver.saveAs(content, `订单`);
        });
      }
      // pdf.save(`${code}.pdf`);
    });
}
        <div
          id="demo"
          className="smModal"
          style={{ width: "800px", margin: "0 auto" }}
        >
          <DownLoad downList={downList} isSuccessFun={isSuccessFun} />
        </div>