SpringBoot--通过form-data上传文件和传递请求参数--方法/实例

蔚落 2023-10-02 21:18 11阅读 0赞

原文网址：[SpringBoot--通过form-data上传文件和传递请求参数--方法/实例\_IT利刃出鞘的博客-CSDN博客][SpringBoot--_form-data_--_IT_-CSDN]

## 简介 ##

本文用示例介绍SpringMVC如何通过form-data请求上传文件和请求数据。

form-data只能传递键值对形式，支持文件和普通的键值对。

## **代码** ##

### **Entity** ###

User.java

package com.example.demo.entity;
    
    import lombok.Data;
    import java.util.List;
    
    @Data
    public class User {
        private String name;
        private Integer age;
        private String[] password;
        private List<Integer> scoreArray;
    }

Account.java

package com.example.demo.entity;
    
    import lombok.Data;
    import java.io.Serializable;
    
    @Data
    public class Account implements Serializable {
        private String phoneNum;
        private String[] emails;
    }

### **Controller** ###

**FormDataController.java**

package com.example.demo.controller;
    
    import com.example.demo.entity.User;
    import io.swagger.annotations.Api;
    import io.swagger.annotations.ApiOperation;
    import org.springframework.web.bind.annotation.PostMapping;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestPart;
    import org.springframework.web.bind.annotation.RestController;
    import org.springframework.web.multipart.MultipartFile;
    
    @Api(tags = "form-data")
    @RequestMapping("/form-data")
    @RestController
    public class FormDataController {
        // @GetMapping也可以
        @ApiOperation("传递数据")
        @PostMapping("normal")
        public User test3(User user) {
            return user;
        }
    
        @ApiOperation("上传文件")
        @PostMapping(value = "file", headers = "content-type=multipart/form-data")
        public String file(@RequestPart MultipartFile file1, @RequestPart MultipartFile[] files) {
            StringBuilder result = new StringBuilder();
            result.append("file1名字：").append(file1.getOriginalFilename()).append("\r\n");
            int i = 0;
            for (MultipartFile file : files) {
                result.append("files[").append(i).append("]名字：").append(file.getOriginalFilename()).append("\r\n");
                i++;
            }
            return result.toString();
        }
    
        // @GetMapping也可以
        @ApiOperation("多个参数")
        @PostMapping("basicType")
        public String basicType(int intVal, Long longVal, String myStr) {
            System.out.println("intVal  : " + intVal);
            System.out.println("longVal : " + longVal);
            System.out.println("myStr   : " + myStr);
            return "Hello world";
        }
    }

## 测试 ##

为方便测试，我用了[knife4j][]。

### **测试1：传递数据** ###

![6c61c9d4d0494bba840a8d601a20217d.png][]

### **测试2**：**上传文件** ###

**knife4j的测试**

![a2f6fe91efd6453086f9ab8825d44cad.png][]

**knife4j不支持文件数组，实际是可以传递多个文件的（下边用postman测试）**

此处用postman，postman支持字符串和文件。

![d4b34c6f085447c69a29090d5b085f0d.png][]

上传文件：

![9fbf2ce95d69451cbcf19e724cf07e61.png][]

### **测试3**：**多个参数** ###

![6c16e750885d480490417335f1d343e0.png][]

后端结果：

![d3a4533798574236acb528ceae6adb68.png][]

**注意**

如果intVal不传，会报错：

![e776906441c345d8be99de2b0bf3c9a3.png][]

后端报错信息为：

2022-09-20 20:08:11.010  WARN 30668 --- [nio-8080-exec-2] .w.s.m.s.DefaultHandlerExceptionResolver : Resolved [org.springframework.web.method.annotation.MethodArgumentTypeMismatchException: Failed to convert value of type 'java.lang.String' to required type 'int'; nested exception is java.lang.NumberFormatException: For input string: ""]

[SpringBoot--_form-data_--_IT_-CSDN]: https://knife.blog.csdn.net/article/details/126954870
[knife4j]: https://knife.blog.csdn.net/article/details/120753090
[6c61c9d4d0494bba840a8d601a20217d.png]: https://img-blog.csdnimg.cn/6c61c9d4d0494bba840a8d601a20217d.png
[a2f6fe91efd6453086f9ab8825d44cad.png]: https://img-blog.csdnimg.cn/a2f6fe91efd6453086f9ab8825d44cad.png
[d4b34c6f085447c69a29090d5b085f0d.png]: https://img-blog.csdnimg.cn/d4b34c6f085447c69a29090d5b085f0d.png
[9fbf2ce95d69451cbcf19e724cf07e61.png]: https://img-blog.csdnimg.cn/9fbf2ce95d69451cbcf19e724cf07e61.png
[6c16e750885d480490417335f1d343e0.png]: https://img-blog.csdnimg.cn/6c16e750885d480490417335f1d343e0.png
[d3a4533798574236acb528ceae6adb68.png]: https://img-blog.csdnimg.cn/d3a4533798574236acb528ceae6adb68.png
[e776906441c345d8be99de2b0bf3c9a3.png]: https://img-blog.csdnimg.cn/e776906441c345d8be99de2b0bf3c9a3.png