compile ('commons-io:commons-io:1.4')
    compile('commons-fileupload:commons-fileupload:1.2.1')

    @Bean(name = "multipartResolver")
    public MultipartResolver multipartResolver(){
        CommonsMultipartResolver resolver = new CommonsMultipartResolver();
        resolver.setDefaultEncoding("UTF-8");
        //resolveLazily屬性啟用是為了推遲文件解析，以在在UploadAction中捕獲文件大小異常
        resolver.setResolveLazily(true);
        resolver.setMaxInMemorySize(40960);
        //上傳文件大小 50M 50*1024*1024
        resolver.setMaxUploadSize(50*1024*1024);
        return resolver;
    }

@Configuration
@ConditionalOnClass({ Servlet.class, StandardServletMultipartResolver.class,
  MultipartConfigElement.class })
@ConditionalOnProperty(prefix = "spring.http.multipart", name = "enabled", matchIfMissing = true)
@EnableConfigurationProperties(MultipartProperties.class)
public class MultipartAutoConfiguration {
 private final MultipartProperties multipartProperties;
 public MultipartAutoConfiguration(MultipartProperties multipartProperties) {
  this.multipartProperties = multipartProperties;
 }
 @Bean
 @ConditionalOnMissingBean({ MultipartConfigElement.class,
   CommonsMultipartResolver.class })
 public MultipartConfigElement multipartConfigElement() {
  return this.multipartProperties.createMultipartConfig();
 }
 @Bean(name = DispatcherServlet.MULTIPART_RESOLVER_BEAN_NAME)
 @ConditionalOnMissingBean(MultipartResolver.class)
 public StandardServletMultipartResolver multipartResolver() {
  StandardServletMultipartResolver multipartResolver = new StandardServletMultipartResolver();
  multipartResolver.setResolveLazily(this.multipartProperties.isResolveLazily());
  return multipartResolver;
 }

spring:
  autoconfigure:
    exclude: org.springframework.boot.autoconfigure.web.servlet.MultipartAutoConfiguration

    @Bean(name = "multipartResolver")
    public MultipartResolver multipartResolver() {
        CommonsMultipartResolver resolver = new CommonsMultipartResolver();
        resolver.setDefaultEncoding("UTF-8");
        return resolver;
    }