檔案上傳SpringBoot後端MultipartFile引數報空問題的解決辦法
阿新 • • 發佈：2020-11-04
最近寫了一個檔案上傳的小demo，就是簡單的前端html頁面，後端controller接收，但是後端一直報錯檔案為null，看了很多文章，有說spring-boot自帶的org.springframework.web.multipart.MultipartFile和Multipart衝突了，要在啟動類中加入@EnableAutoConfiguration(exclue={MultipartAutoConfiguration.class})，有說要在MultipartFile引數前加上@RequestParam(“file”)以表明該引數型別是檔案型別，還有說是前端表單沒有設定enctype=“multipart/form-data”，參照上面方法我還是沒有解決問題，後來更換了spring-boot版本就好了，程式碼如下：
1、pom.xml(注意我這裡用的是2.0.4版本)
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.RELEASE</version>
</parent>
<groupId>org.sang</groupId>
<artifactId>chapter01</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>2、upload.html頁面
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form action="/upload" method="post" enctype="multipart/form-data"> <input type="file" name="uploadFile" value="請選擇檔案"> <input type="submit" value="上傳"> </form> </body> </html>
3、後端controller
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.UUID;
@RestController
public class FileUploadController {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd");
@PostMapping("upload")
public String upload(MultipartFile uploadFile,HttpServletRequest req){
String realPath = req.getSession().getServletContext().getRealPath("/uploadFile");
String format = sdf.format(new Date());
File folder = new File(realPath+format);
if(!folder.isDirectory()){
folder.mkdirs();
}
String oldName = uploadFile.getOriginalFilename();
String newName = UUID.randomUUID().toString()+oldName.substring(oldName.lastIndexOf("."),oldName.length());
try{
uploadFile.transferTo(new File(folder,newName));
String path = req.getScheme()+"://"+req.getServerName()+":"+req.getServerPort()+"/uploadFile/"+format+newName;
return path;
}catch (IOException e){
e.printStackTrace();
}
return "上傳失敗";
}
}
到此這篇關於檔案上傳SpringBoot後端MultipartFile引數報空問題的解決辦法的文章就介紹到這了,更多相關SpringBoot MultipartFile引數報空 內容請搜尋我們以前的文章或繼續瀏覽下面的相關文章希望大家以後多多支援我們！