前端打印功能(vue +springboot)

后端

依赖

依赖 一个是用模版生成对应的pdf,一个是用来将pdf转成图片需要的

      <!--打印的-->
        <dependency>
            <groupId>net.sf.jasperreports</groupId>
            <artifactId>jasperreports</artifactId>
        </dependency>

        <dependency>
            <groupId>org.apache.pdfbox</groupId>
            <artifactId>pdfbox</artifactId>
            <version>3.0.0</version>
        </dependency>

所需的文件资源 jasper是模版,然后font是pdf转图片的时候需要的字体

由于有资源 所以pom配置俩包下面不允许压缩

    <build>
        <resources>
            <resource>
                <targetPath>${project.build.directory}/classes</targetPath>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
                <excludes>
                    <exclude>**/*.jasper</exclude>
                    <exclude>**/*.jrxml</exclude>
                    <exclude>**/*.TTF</exclude>
                </excludes>
            </resource>
            <resource>
                <targetPath>${project.build.directory}/classes</targetPath>
                <directory>src/main/resources</directory>
                <filtering>false</filtering>
                <includes>
                    <include>**/*.jasper</include>
                    <include>**/*.jrxml</include>
                    <include>**/*.TTF</include>
                </includes>
            </resource>
        </resources>
    </build>

生成pdf的方法

用到的实体类

package com.xueyi.common.core.utils.print.dto;

import lombok.Data;

@Data
public class PdfInfoDto {
    private Integer height;
    private Integer width;
    private byte[] pdfBytes;
}

生成pdf的方法

package com.xueyi.common.core.utils.print;

import com.xueyi.common.core.utils.print.dto.PdfInfoDto;
import net.sf.jasperreports.engine.*;
import net.sf.jasperreports.engine.export.JRPdfExporter;
import net.sf.jasperreports.engine.util.JRLoader;
import net.sf.jasperreports.export.SimpleExporterInput;
import net.sf.jasperreports.export.SimpleOutputStreamExporterOutput;
import net.sf.jasperreports.export.SimplePdfExporterConfiguration;
import org.springframework.core.io.ClassPathResource;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;

public class PrintUtil {

    public static PdfInfoDto printPDF(String modelName, HashMap hashMap) throws IOException, JRException {
        // 获取模板路径
        ClassPathResource classPathResource = new ClassPathResource("/jasper/"+modelName+".jasper");


        // 获取模板输入流
        InputStream inputStream = classPathResource.getInputStream();
        // 读取模板
        JasperReport report = (JasperReport) JRLoader.loadObject(inputStream);
        //数据库数据填充报表
        JasperPrint jprint = JasperFillManager.fillReport(report, hashMap,new JREmptyDataSource());

       DefaultJasperReportsContext defaultJasperReportsContext=DefaultJasperReportsContext.getInstance();
//        defaultJasperReportsContext.setProperty("net.sf.jasperreports.fonts.STSong-Light", "path/to/STSong-Light.ttf");

        //创建导出对象
        JRPdfExporter exporter = new JRPdfExporter(defaultJasperReportsContext);

        //设置要导出的流
        exporter.setExporterInput(new SimpleExporterInput(jprint));
        ByteArrayOutputStream byteArrayOutputStream=new ByteArrayOutputStream();
        exporter.setExporterOutput(new SimpleOutputStreamExporterOutput(byteArrayOutputStream));
        SimplePdfExporterConfiguration configuration = new SimplePdfExporterConfiguration();
        configuration.setCreatingBatchModeBookmarks(true);
        exporter.setConfiguration(configuration);
        // 导出pdf
        exporter.exportReport();
        byte[] bytes=byteArrayOutputStream.toByteArray();
        byteArrayOutputStream.close();

        PdfInfoDto pdfInfo=new PdfInfoDto();
        pdfInfo.setPdfBytes(bytes);
        pdfInfo.setHeight(jprint.getPageHeight());
        pdfInfo.setWidth(jprint.getPageWidth());
        return pdfInfo;
    }

}

pdf转图片

用到的实体类

package com.xueyi.common.core.utils.print.dto;

import lombok.Data;

@Data
public class ImageInfoDto {
    private Integer height;
    private Integer width;
    private byte[] imageBytes;
}

package com.xueyi.common.core.utils.print;


import com.xueyi.common.core.utils.print.dto.ImageInfoDto;
import org.apache.pdfbox.Loader;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class Pdf2PngUtil {

    public static List<ImageInfoDto> pdf2png(byte[] bytes) throws IOException {
          ArrayList<ImageInfoDto> list=new ArrayList();
            PDDocument doc=Loader.loadPDF(bytes);
            PDFRenderer renderer = new PDFRenderer(doc);
            int pageCount = doc.getNumberOfPages();
            for (int i = 0; i < pageCount; i++) {
                // dpi为144，越高越清晰，转换越慢
                BufferedImage image = renderer.renderImageWithDPI(i, 144); // Windows native DPI
                ByteArrayOutputStream byteArrayOutputStream=new ByteArrayOutputStream();
                ImageIO.createImageOutputStream(byteArrayOutputStream);
                ImageIO.write(image, "png", byteArrayOutputStream);

                ImageInfoDto imageInfo=new ImageInfoDto();
                imageInfo.setHeight(image.getHeight());
                imageInfo.setWidth(image.getWidth());
                imageInfo.setImageBytes(byteArrayOutputStream.toByteArray());
                list.add(imageInfo);
                byteArrayOutputStream.close();
            }
            doc.close();
            return  list;
    }
}

使用(用的打印模版是带参数的 ,参数是aaa)

返回类

@Data
public class PrintDto {
    @Serial
    private static final long serialVersionUID = 1L;
    private String jasperName;
    private HashMap hashMap;
    private List<ImageInfoDto> imageInfoDtoList;
    private PdfInfoDto pdfInfoDto;
}

使用

    @PostMapping("/print")
    public AjaxResult print(@RequestBody TransSchedulerQuery transSchedulerQuery) throws IOException, JRException {
        PrintDto printDto=new PrintDto();
        printDto.setJasperName(transSchedulerQuery.getJasperName());
        HashMap hashMap=new HashMap();
        hashMap.put("aaa","你看得到吗?");
        printDto.setPdfInfoDto(PrintUtil.printPDF(transSchedulerQuery.getJasperName(),hashMap));
        printDto.setImageInfoDtoList(Pdf2PngUtil.pdf2png(printDto.getPdfInfoDto().getPdfBytes()));
        return  AjaxResult.success(printDto);
    }

总结

后端的思路其实很简单,就是用带参数的打印模版,然后把对应参数送进去生成pdf,由于前端需要图片和pdf两种,所以又把生成的pdf转图片生成了一下图片的list.然后不管事pdf和图片,都是直接把文件本身传递回去了,没有存到本地,用url的方法.直接把文件的byte数组传递到前端了(一般序列化的方式就是base64,所以json序列化的时候自动转好了的前端接到的是字符串形式的)

前端

前端其实很简单,就是把得到的文件信息拿到,转成blob形式,然后预览一下.唯一的问题就是拿到的字符串需要进行转码,从base64变回byte数组.因为要有预览的效果,所以一直尝试前端pdf转换然后要自定义打印啥的(Lodop),用了很多无用的代码,后续定下来打印就调用浏览器的打印啥的,那个打印按钮有打印前和打印后的回调函数的,已经满足需求了.

export function base64ToByteArray(base64String: string): Uint8Array {
  const binaryString = atob(base64String);
  const length = binaryString.length;
  const bytes = new Uint8Array(length);

  for (let i = 0; i < length; i++) {
    bytes[i] = binaryString.charCodeAt(i);
  }

  return bytes;
}

页面

<template>
  <BasicModal  v-bind="$attrs" :width="ModalWidthEnum.COMMON" @register="registerModal" :canFullscreen="false" :title="variable.title" :height="400"   :okText="t('public.button.print')"   @ok="handleSubmit" >


    <div style="margin-top: 5px;text-align: center;">
      <span> {{t("public.describe.all")}}{{variable.imagesUrlList.length}}{{t("public.describe.page")}}{{t("public.describe.clickToTurnOver")}}</span>
    </div>

    <iframe ref="pdfFrameRef" :src="variable.pdfUrl" style="display: none"></iframe>

    <Row ref="rowRef">
<!--      <Col :span="1" >-->
<!--        <div style="height: 100%;">-->
<!--          <CaretLeftOutlined style="position: absolute;top: 45%"/>-->
<!--        </div>-->
<!--      </Col>-->
      <Col :span="24">
        <div style="border: black 1px solid;" >
          <Image :src="variable.imagesUrlList[0]" width="100%" :preview="variable.preview" @click="variable.preview = true"/>
          <div style="display: none">
            <Image.PreviewGroup :preview="{ visible:variable.preview, onVisibleChange: vis => (variable.preview = vis) }">
              <Image v-for="(item) in variable.imagesUrlList"  :src="item" width="100%" />
            </Image.PreviewGroup>
          </div>

        </div>

      </Col>
<!--      <Col :span="1" >-->
<!--        <div style="height: 100%;">-->
<!--          <CaretRightOutlined style="position: absolute;top: 45%"/>-->
<!--        </div>-->

<!--      </Col>-->

    </Row>










  </BasicModal>
</template>

<script setup lang="ts">
import {reactive, ref} from 'vue';
import {useMessage} from '@/hooks/web/useMessage';
import {BasicModal, useModalInner} from '@/components/Modal';
import {useI18n} from "@/hooks/web/useI18n";
import {ModalWidthEnum} from "@/enums";
import {Image,Row,Col,} from 'ant-design-vue';
// 定义国际化
const { t } = useI18n();
const emit = defineEmits(['success']);
const {createMessage} = useMessage();
const isUpdate = ref(true);
import {base64ToByteArray} from "@/utils/commonFunctions/commonFunctions";
/** 标题初始化 */
const variable = reactive<any>({
  ids: [],
  fatherParam:{},
  title:"",
  pdfUrl:null,
  pdfBlob:null,
  imagesUrlList:[],
  currentIndex:0,
  currentHeight:0,
  preview:false,
  afterPrintFunction:null
});

const pdfFrameRef=ref()
const rowRef=ref()


const [registerModal, {setModalProps, closeModal,changeOkLoading,changeLoading}] = useModalInner(async (data) => {

  variable.fatherParam=JSON.parse(JSON.stringify(data.fatherParam))
  variable.afterPrintFunction=data.afterPrintFunction
  variable.title=data.fatherParam.title
  variable.imagesUrlList=[]
  variable.currentIndex=0
  variable.preview=false
  //有图片的情况
  if (data.fatherParam.data.imageInfoDtoList?.length>0){
    variable.currentHeight=variable.fatherParam.data.imageInfoDtoList[0].height
    variable.pdfBlob = new Blob([base64ToByteArray(variable.fatherParam.data?.pdfInfoDto?.pdfBytes)], { type: 'application/pdf'});
    variable.pdfUrl= window.URL.createObjectURL(variable.pdfBlob)
    variable.fatherParam.data.imageInfoDtoList.forEach(item=>{
      const blob1 = new Blob([base64ToByteArray(item.imageBytes)], { type: 'image/png'});
      variable.imagesUrlList.push(window.URL.createObjectURL(blob1))
    })
  }


});


// const getPrintDevice = () => {
//   var loop = getLodop(); // 创建一个LODOP对象
//   let counter = loop.GET_PRINTER_COUNT(); // 获取打印机个数
//   //初始化下printNameList打印数组
//   variable.printDeviceList = [];
//   for (let i = 0; i < counter; i++) {
//     //将打印机存入printList数组中
//     variable.printDeviceList.push({name:loop.GET_PRINTER_NAME(i),value:i});
//   }
//
//   //获取默认打印机并设置
//   var defaultName =loop.GET_PRINTER_NAME(-1);
//   variable.printDeviceList.forEach(item=>{
//     if(item.name==defaultName){
//       variable.printDevice=item.value
//     }
//   })
// }

// const doPrint = () => {
//   var LODOP = getLodop(); // 创建一个LODOP对象
//   // LODOP.ADD_PRINT_IMAGE(0, 0, "<img>", "EMF", variable.pdfUrl);
//   LODOP.PRINT_INIT("打印控件功能演示_Lodop功能_按网址打印");
//   let base64="data:image/png;base64,"+variable.fatherParam.data.imageListByte[0]
//   LODOP.ADD_PRINT_IMAGE(0,0,"100%","100%",base64);
//   console.log(base64)
//   LODOP.PRINT();
// }


// // 创建 LODOP 实例
// function getLodop() {
//   let LODOP;
//   if (window.LODOP) {
//     LODOP = window.LODOP;
//   } else if (window.parent.LODOP) {
//     LODOP = window.parent.LODOP;
//   } else {
//     LODOP = (function () {
//       var LODOP = null;
//       var s = document.createElement('script');
//       s.src = '/LODOPfuncs.js';
//       s.id = 'LODOPfuncs';
//       s.type = 'text/javascript';
//       document.getElementsByTagName('head')[0].appendChild(s);
//       document.onpropertychange = function (e) {
//         if (e.propertyName === 'LODOP') {
//           LODOP = e.srcElement.LODOP;
//         }
//       };
//       return LODOP;
//     })();
//   }
//   return LODOP;
// }

/** 提交按钮 */
async function handleSubmit() {
  pdfFrameRef.value.contentWindow.print();
  window.onafterprint = afterPrint;
}

/**
 * 浏览器打印的回调
 */
const afterPrint = async () =>  {
  variable.afterPrintFunction()
}

</script>

效果

原文地址：https://blog.csdn.net/qigaidawang111/article/details/142861356

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