springboot笔记-文件上传

使用 Spring Boot 和 Thymeleaf 上传文件

Spring Boot 利用 MultipartFile 的特性来接收和处理上传的文件，本示例前端页面使用 Thymeleaf 来处理。

快速上手:

1、添加依赖包

    <dependency>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-web</artifactId>

    </dependency>

    <dependency>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-thymeleaf</artifactId>

    </dependency>

2、application.properties配置信息

#支持的最大文件

spring.servlet.multipart.max-file-size=100MB

#文件请求最大限制

spring.servlet.multipart.max-request-size=100MB

#除过以上配置，常用的配置信息如下：
spring.servlet.multipart.enabled=true，是否支持 multipart 上传文件
spring.servlet.multipart.file-size-threshold=0，支持文件写入磁盘
spring.servlet.multipart.location=，上传文件的临时目录
spring.servlet.multipart.max-file-size=10Mb，最大支持文件大小
spring.servlet.multipart.max-request-sizee=10Mb，最大支持请求大小
spring.servlet.multipart.resolve-lazily=false，是否支持 multipart 上传文件时懒加载

3、启动类

@SpringBootApplication

public class FileUploadWebApplication {

    public static void main(String[] args) throws Exception {

        SpringApplication.run(FileUploadWebApplication.class, args);

    }

    //Tomcat large file upload connection reset

    @Bean

    public TomcatServletWebServerFactory tomcatEmbedded() {

        TomcatServletWebServerFactory tomcat = new TomcatServletWebServerFactory();

        tomcat.addConnectorCustomizers((TomcatConnectorCustomizer) connector -> {

            if ((connector.getProtocolHandler() instanceof AbstractHttp11Protocol<?>)) {

                //-1 means unlimited

                ((AbstractHttp11Protocol<?>) connector.getProtocolHandler()).setMaxSwallowSize(-);

            }

        });

        return tomcat;

    }

}

TomcatServletWebServerFactory() 方法主要是为了解决上传文件大于 10M 出现连接重置的问题

4、简单前端页面:

　　单个文件上传页面 upload.html:

    <!DOCTYPE html>

    <html xmlns:th="http://www.thymeleaf.org">

    <body>

    <h1>Spring Boot file upload example</h1>

    <form method="POST" action="/upload" enctype="multipart/form-data">

        <input type="file" name="file" /><br/><br/>

        <input type="submit" value="Submit" />

    </form>

    </body>

    </html>

　　多个文件上传页面 uploadMore.html:

<!DOCTYPE html>

    <html xmlns:th="http://www.thymeleaf.org">

    <body>

    <h1>Spring Boot files upload example</h1>

    <form method="POST" action="/uploadMore" enctype="multipart/form-data">

        <input type="file" name="file" /><br/><br/>

        <input type="file" name="file" /><br/><br/>

        <input type="file" name="file" /><br/><br/>

        <input type="submit" value="Submit" />

    </form>

    </body>

    </html>

上传结果页面：uploadStatus.html

<!DOCTYPE html>

    <html lang="en" xmlns:th="http://www.thymeleaf.org">

    <body>

    <h1>Spring Boot - Upload Status</h1>

    <div th:if="${message}">

        <h2 th:text="${message}"/>

    </div>

    </body>

    </html>

5、后台上传控制类

@Controller

public class UploadController {

    //文件存储目录

    private String UPLOAD_PATH="E://temp//";

    //跳转上传页面

    @RequestMapping("/")

    public String index() {

        return "upload";

    }

    @GetMapping("/more")

    public String uploadMore() {

        return "uploadMore";

    }

    //多个文件上传

    @RequestMapping("/uploadMore")

    public String moreFileUpload(@RequestParam("file") MultipartFile[] files,RedirectAttributes redirectAttrs) {

        if(files.length ==0) {

            redirectAttrs.addFlashAttribute("message", "Please select a file to upload");

            return "redirect:uploadStatus";

        }

        for(MultipartFile file :files) {

            try {

                byte[] bytes = file.getBytes();

                Path path = Paths.get(UPLOAD_PATH+file.getOriginalFilename());

                Files.write(path, bytes);

            } catch (IOException e) {

                e.printStackTrace();

            }

        }

        redirectAttrs.addFlashAttribute("message",

                "You successfully uploaded all files");

        return "redirect:/uploadStatus";

    }

    //单个文件上传

    @PostMapping("/upload")

    public String singleFileUpload(@RequestParam("file") MultipartFile file,RedirectAttributes redirectAttrs) {

        if(file.isEmpty()) {

            redirectAttrs.addFlashAttribute("message", "Please select a file to upload");

            return "redirect:uploadStatus";

        }

        try {

            byte[] bytes = file.getBytes();

            Path path = Paths.get(UPLOAD_PATH+file.getOriginalFilename());

            Files.write(path, bytes);

            redirectAttrs.addFlashAttribute("message",

                        "You successfully uploaded '" + file.getOriginalFilename() + "'");

        } catch (IOException e) {

            e.printStackTrace();

        }

        return "redirect:/uploadStatus";

    }

    //跳转结果页面

    @RequestMapping("/uploadStatus")

    public String uploadStatus() {

        return "uploadStatus";

    }

}

6、运行启动类：FileUploadWebApplication

在浏览器访问：

　　多个文件上传：

OK ，上传成功。

巴特西

springboot笔记-文件上传

最新文章

热门文章