将html页面保存成图片,图片写入pdf的实现方法(推荐)

html2canvas(document.body, { //截图对象     //此处可配置详细参数     onrendered: function(canvas) { //渲染完成回调canvas       canvas.id = "mycanvas";        // 生成base64图片数据       var dataUrl = canvas.toDataURL('image/png');  //指定格式，也可不带参数       var formData = new FormData(); //模拟表单对象       formData.append("imgData", convertBase64UrlToBlob(dataUrl), "123.png"); //写入数据       var xhr = new XMLHttpRequest(); //数据传输方法       xhr.open("POST", "../bulletin/exportPdf"); //配置传输方式及地址       xhr.send(formData);       xhr.onreadystatechange = function(){ //回调函数         if(xhr.readyState == 4){            if (xhr.status == 200) {               var back = JSON.parse(xhr.responseText);               if(back.success == true){                 alertBox({content: 'Pdf导出成功！',lock: true,drag: false,ok: true});               }else{                 alertBox({content: 'Pdf导出失败！',lock: true,drag: false,ok: true});               }            }         }       };     }});   //将以base64的图片url数据转换为Blobfunction convertBase64UrlToBlob(urlData){  //去掉url的头，并转换为byte  var bytes=window.atob(urlData.split(',')[1]);      //处理异常,将ascii码小于0的转换为大于0  var ab = new ArrayBuffer(bytes.length);  var ia = new Uint8Array(ab);  for (var i = 0; i < bytes.length; i++) {    ia[i] = bytes.charCodeAt(i);  }  return new Blob( [ab] , {type : 'image/png'});}

String base64 = Img.split(",")[1];BASE64Decoder decode = new BASE64Decoder(); byte[] imgByte = decode.decodeBuffer(base64);

@RequestMapping("/exportPdf")public @ResponseBody void exportPdf(MultipartHttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {  ResultData result = new ResultData();  //自定义结果格式  String filePath = "c://exportPdf2.pdf";  String imagePath = "c://exportImg2.bmp";  Document document = new Document();   try{    Map getMap = request.getFileMap();    MultipartFile mfile = (MultipartFile) getMap.get("imgData"); //获取数据    InputStream file = mfile.getInputStream();    byte[] fileByte = FileCopyUtils.copyToByteArray(file);          FileImageOutputStream imageOutput = new FileImageOutputStream(new File(imagePath));//打开输入流    imageOutput.write(fileByte, 0, fileByte.length);//生成本地图片文件    imageOutput.close();          PdfWriter.getInstance(document, new FileOutputStream(filePath)); //itextpdf文件//    document.setPageSize(PageSize.A2);    document.open();    document.add(new Paragraph("JUST TEST ..."));    Image image = Image.getInstance(imagePath); //itext-pdf-image    float heigth = image.getHeight();         float width = image.getWidth();         int percent = getPercent2(heigth, width);  //按比例缩小图片        image.setAlignment(Image.MIDDLE);         image.scalePercent(percent+3);    document.add(image);    document.close();      result.setSuccess(true);    operatelogService.addOperateLogInfo(request, "导出成功：成功导出简报Pdf");  }catch (DocumentException de) {    System.err.println(de.getMessage());  }  catch (Exception e) {    e.printStackTrace();    result.setSuccess(false);    result.setErrorMessage(e.toString());    try {      operatelogService.addOperateLogError(request, "导出失败：服务器异常");    } catch (Exception e1) {      e1.printStackTrace();    }  }  response.getWriter().print(JSONObject.fromObject(result).toString());}private static int getPercent2(float h, float w) {  int p = 0;  float p2 = 0.0f;  p2 = 530 / w * 100;  p = Math.round(p2);  return p;}