多文件上传,后端接收到多次请求
vue实现

<el-upload
        class="upload-demo"
        action="http://10.240.46.88:8081/upload1"
        :on-preview="handlePreview"
        :on-remove="handleRemove"
        :multiple="multiple"
        :limit="3"
        :on-exceed="handleExceed"
        :on-success="sucess"
        :file-list="fileList">
      <el-button size="small" type="primary">点击上传</el-button>
      <div slot="tip" class="el-upload__tip">只能上传jpg/png文件,且不超过500kb</div>
    </el-upload>
springboot后台@PostMapping("/upload")
    public String upload(@RequestParam("file") MultipartFile file) {
        System.out.println("上传文件方法触发了");
        //判断非空
        if (file.isEmpty()) {
            return "上传的文件不能为空";
        }
        try {
            // 测试MultipartFile接口的各个方法
//            logger.info("[文件类型ContentType] - [{}]",file.getContentType());
//            logger.info("[文件组件名称Name] - [{}]",file.getName());
//            logger.info("[文件原名称OriginalFileName] - [{}]",file.getOriginalFilename());
//            logger.info("[文件大小] - [{}]",file.getSize());
//            logger.info(this.getClass().getName()+"图片路径:"+path);
            String path = "/Users/lijianxi/projects/javaproject/springlearn/src/main/resources/";
            File f = new File(path);
            // 如果不存在该路径就创建
            if (!f.exists()) {
                f.mkdir();
            }
            File dir = new File(path + file.getOriginalFilename());
            // 文件写入
            file.transferTo(dir);
            return "上传单个文件成功";
        } catch (Exception e) {
            e.printStackTrace();
            return "上传单个文件失败";
        }
    }

2.多文件上传,后端接收到一次请求

vue实现

<el-upload
        class="upload-demo"
        ref="upload"
        action="http://10.240.46.88:8081/upload2"
        :on-preview="handlePreview"
        :on-remove="handleRemove"
        :file-list="fileList"
        :http-request="uploadFile"
        :auto-upload="false">
      <el-button slot="trigger" size="small" type="primary">选取文件</el-button>
      <el-button style="margin-left: 10px;" size="small" type="success" @click="submitUpload">上传到服务器</el-button>
      <div slot="tip" class="el-upload__tip">只能上传jpg/png文件,且不超过500kb</div>
    </el-upload>


springboot后台

@PostMapping("/upload2")
    public String upload2(@RequestParam("file")MultipartFile[] file){
        System.out.println("-----22222--"+file.length);
        String path = "/Users/lijianxi/projects/javaproject/springlearn/src/main/resources/";
        if(file!=null&file.length>0) {
            for (MultipartFile multipartFile : file) {
                String fileName = multipartFile.getOriginalFilename();
                File file1 = new File(path + fileName);
                try {
                    multipartFile.transferTo(file1);
                } catch (IOException e) {
                    e.printStackTrace();
                    return "上传失败";
                }
                System.out.println("");
            }
        }
        System.out.println("上传成功");
        return "多文件上传成功";
    }

多文件上传时,默认的vue组件会将文件进行多次请求后端,为了可以实现一次请求,需要手动改造代码

html部分

修改:auto-upload="false"属性为false,阻止组件的自动上传
:http-request="uploadFile"覆盖上传事件
@click="submitUpload",给上传按钮绑定事件
js部分

在data中设置一个变量fileData
在方法中设置FormData的格式
通过ajax发送请求,携带参数为fileData

上传过程中报错:

TypeError: 'append' called on an object that does not implement interface FormData.
解决方法:

//报错请加入以下三行,则ajax提交无问题
cache: false,
processData: false,
contentType: false,

 

参考文章:http://blog.ncmem.com/wordpress/2023/12/11/springbootvue实现多文件上传/