后端MultipartFile接收文件转Base64

@

目录

• 背景说明
• 测试案例+代码
  • 测试方法1
  • 测试方法2

背景说明

最开始写的版本代码删改较多且无法运行，在其他博主给我指出问题及改进措施之后，下面的是最新汇总并测试结果有效的接口，编写日期：2022年08月12日。

下面代码是后端接收到文件，并把文件转为Base64，而不是前端传Base64传递给后端，这点需注意！
如果想前端传递Base64的需自己找文章，主要：网上的部分文章转Base64没给pom依赖，会导致找不到类，我这个是能够进行编译Base64的工具包，也注明了import的引入，记录改文章也是方便后续我自己查看而已。

测试案例+代码

测试接口1和测试接口2没太大差别，一个用了buffer缓存一个没用到而已，最终结果打印一致。

pom依赖

 <dependency><groupId>commons-codec</groupId><artifactId>commons-codec</artifactId><version>1.10</version>
</dependency>

测试方法1

测试方法1

import com.example.demo.bean.OperateTeacherReq;
import com.example.demo.bean.TeacherReq;
import com.example.demo.config.LogAnnotation;
import com.example.demo.mapper.TeacherMapper;
import com.example.demo.response.Response;
import org.apache.commons.codec.binary.Base64;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
@RestController
public class Controller {//测试方法1@RequestMapping(value = "uploadLogo")public void uploadLogo(@RequestParam("file") MultipartFile fileImage) {String base64EncoderImg = "";try {base64EncoderImg = Base64.encodeBase64String(fileImage.getBytes());base64EncoderImg = "data:image/png;base64," + base64EncoderImg;System.out.println(base64EncoderImg);} catch (IOException e) {e.printStackTrace();}}}    

用postman或者apipost模拟发送接口测试结果，随便上传一个excel文件

会议详情

重要信息

• 大会官网：https://ais.cn/u/vEbMBz

大会介绍

由厦门大学与桂林理工大学联合主办的第五届材料化学与复合材料国际学术会议（MCCM 2024）将于2024年12月27-29日在厦门隆重召开。会议主要围绕材料化学与复合材料等研究领域展开讨论。会议旨在为从事材料化学与复合材料研究的专家学者、工程技术人员、技术研发人员提供一个共享科研成果和前沿技术，了解学术发展趋势，拓宽研究思路，加强学术研究和探讨，促进学术成果产业化合作的平台。大会诚邀国内外高校、科研机构专家、学者，企业界人士及其他相关人员参会交流！

测试方法2

测试方法2

import com.example.demo.bean.OperateTeacherReq;
import com.example.demo.bean.TeacherReq;
import com.example.demo.config.LogAnnotation;
import com.example.demo.mapper.TeacherMapper;
import com.example.demo.response.Response;
import org.apache.commons.codec.binary.Base64;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
@RestController
public class Controller {//测试方法2@RequestMapping(value = "uploadLogo2")public void uploadLogo2(@RequestParam("file") MultipartFile fileImage) {String base64EncoderImg = "";byte[] buffer = null;try {InputStream inputStream = fileImage.getInputStream();ByteArrayOutputStream bos = new ByteArrayOutputStream();byte[] b = new byte[1024];int n;while ((n = inputStream.read(b)) != -1){bos.write(b, 0, n);}inputStream.close();bos.close();buffer = bos.toByteArray();base64EncoderImg = Base64.encodeBase64String(buffer);base64EncoderImg = "data:image/png;base64," + base64EncoderImg;System.out.println(base64EncoderImg);} catch (IOException e) {e.printStackTrace();}}
}

用postman或者apipost模拟发送接口测试结果，随便上传一个excel文件

打印2个测试接口输出结果相同：
代码输出格式为："data:image/png;base64," + base64EncoderImg;，结果和代码一致，确认有效
data:image/png;base64,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