河源网站建设网络营销岗位描述的内容
文章目录
- 前言
- 技术栈
- 项目目录
- 前端实现
- index.html
- script.js
- 后端实现
- MultipartFile 介绍
- 配置文件
- 实体类
- Controller
- Mapper
- Service
- 拦截器
- 测试结果展示
前言
最近有一个需求需要实现图片上传，因此，本人找到了一个可以快速实现该功能的插件mini-upload-form。在此记录分享一下使用过程。
mini-upload-form的Github跳转
将程序从github拉下后，前端页面index.html可简单修改后直接使用，我们的精力主要放在后端实现。
技术栈
- jdk1.8.0_162
- maven-3.3.9
- mybatis-plus
项目目录
需将mini-upload-from中assets文件下的资源引入自己项目中。除外还需引入bootstrap和jquery。
前端实现
index.html
<!DOCTYPE html>
<html>
<head><meta charset="utf-8"/><title>Mini Ajax File Upload Form</title><!-- The main CSS file --><link href="mini-upload-form/css/style.css" rel="stylesheet"/><link href="bootstrap/css/bootstrap.css" rel="stylesheet"/>
</head><body>
<div class="row"><div class="col align-self-start"><div><h4>上传照片：</h4></div><div class="d-flex flex-row flex-wrap mb-5" id="upload-img-container"><p>暂无</p></div></div>
</div>
<div class="row"><div class="col align-self-start"><form id="upload" method="post" action="/file/upload" enctype="multipart/form-data"><div id="note" class="text-white"></div><div id="drop">拖到此区域<a>浏览本地</a><input id="uploadFile" type="file" name="file" multiple/></div><ul><!-- The file uploads will be shown here --></ul></form><div class="col align-self-start"></div><div class="row"><div class="col align-self-start"><div class="text-center"><a type="button" id="submit-file-btn" class="text-center btn btn-info text-white">提交</a></div></div></div></div>
</div><script src="js/jquery-1.11.3.js"></script>
<script src="bootstrap/js/bootstrap.js"></script><script src="mini-upload-form/js/jquery.knob.js"></script>
<!-- jQuery File Upload Dependencies -->
<script src="mini-upload-form/js/jquery.ui.widget.js"></script>
<script src="mini-upload-form/js/jquery.iframe-transport.js"></script>
<script src="mini-upload-form/js/jquery.fileupload.js"></script>
<!-- Our main JS file -->
<script src="mini-upload-form/js/script.js"></script></body>
</html>
script.js
本文还实现了上传成功后回写到前端页面，所以需修改script.js添加提交成功后回调函数。
// Automatically upload the file once it is added to the queuevar jqXHR = data.submit().success(function (result) {var status = result['code'];var fileUri = result['fileUri'];var fileId = result['fileId'];var originFileName = result['originFileName'];if (status!='200'){data.context.addClass('error');numError++;}else{images.push(fileId)localStorage.setItem('cd_files', JSON.stringify(images))numSuccess++;$("#upload-img-container>p:nth-child(1)").remove()const imageHTML = "<div style='width:100px;height:100px;margin:.5rem;text-align:center'>"+"<image class='rounded' style='width:100%;height:100%' src="+staticServer + fileUri +" alt=>"+"<p class='text-center text-muted ' style='word-wrap: break-word;'>"+originFileName+"</p></div>";$("#upload-img-container").append(imageHTML)}updateNote();});
// Update the notefunction updateNote() {if($('#note').length)$('#note').html('<span>' + numSuccess + '</span> 个成功上传.<br /><span id="note-error">' + numError + '</span> 个上传失败.' + (numError > 0 ? ' <a href="#" id="btn-retry"> (Retry all)</a>' : ''));}
后端实现
MultipartFile 介绍
MultipartFile是SpringMVC提供简化上传操作的工具类。
在不使用框架之前，都是使用原生的HttpServletRequest来接收上传的数据，文件是以二进制流传递到后端的，然后需要我们自己转换为File类。使用了MultipartFile工具类之后，我们对文件上传的操作就简便许多了。
MultipartFile接口方法
package org.springframework.web.multipart;import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import org.springframework.core.io.InputStreamSource;
import org.springframework.core.io.Resource;
import org.springframework.lang.Nullable;
import org.springframework.util.FileCopyUtils;public interface MultipartFile extends InputStreamSource {//getName() 返回参数的名称String getName();//获取源文件的昵称@NullableString getOriginalFilename();//getContentType() 返回文件的内容类型@NullableString getContentType();//isEmpty() 判断是否为空，或者上传的文件是否有内容boolean isEmpty();//getSize() 返回文件大小 以字节为单位long getSize();//getBytes() 将文件内容转化成一个byte[] 返回byte[] getBytes() throws IOException;//getInputStream() 返回InputStream读取文件的内容InputStream getInputStream() throws IOException;default Resource getResource() {return new MultipartFileResource(this);}//transferTo(File dest) 用来把 MultipartFile 转换换成 Filevoid transferTo(File var1) throws IOException, IllegalStateException;default void transferTo(Path dest) throws IOException, IllegalStateException {FileCopyUtils.copy(this.getInputStream(), Files.newOutputStream(dest));}
}配置文件
# server
server.port=8010# datasource
spring.datasource.url=jdbc:mysql://xxxx:3306/upload?characterEncoding=utf-8&useSSL=false
spring.datasource.username=***
spring.datasource.password=****
spring.datasource.driver-class-name=com.mysql.jdbc.Driver# upload size setting
spring.servlet.multipart.max-file-size=30MB
spring.servlet.multipart.max-request-size=30MB file.upload.dir=D://upload
file.visit.path=upload
实体类
图片存储实体类SysFile
@Data
@Builder
@TableName("sys_file")
public class SysFile {private String fileId;private String mediaType;private String fileFormat;private String filePath;private String originalName;private Long fileSize;private Integer imageWidth;private Integer imageHeight;private String createUserId;private Date createDate;private String updateUserId;private Date updateDate;
}
Controller
@RestController
@RequestMapping("/file")
public class FileUploadController {@Autowiredprivate LocalStorageService localStorageService;@RequestMapping("/upload")public AjaxResult upload(@RequestParam("file") MultipartFile file) throws Exception {try {if (file.isEmpty()) {throw new RuntimeException("上传文件不能为空");}return localStorageService.upload(file);} catch (Exception e) {e.printStackTrace();return AjaxResult.error("文件上传失败");}}
}
Mapper
SysFileMapper
@Mapper
public interface SysFileMapper extends BaseMapper<SysFile> {
}
Service
SysFileService
public interface SysFileService extends IService<SysFile> {
}@Service
public class sysFileServiceImpl extends ServiceImpl<SysFileMapper, SysFile> implements SysFileService {
}
LocalStorageService
@Slf4j
@Service("localStorageService")
public class LocalStorageService {@Autowiredprivate SysFileService sysFileService;@Value("${file.upload.dir}")private String uploadDir;@Value("${file.visit.path:upload}")private String visitPath;private static final String[] ALLOW_FILE_TYPES = { "jpg", "jpeg", "png"};public AjaxResult upload(MultipartFile file) throws Exception {String contentType = file.getContentType().toLowerCase();boolean allowType = false;for (String allowFileType : ALLOW_FILE_TYPES) {if(contentType.contains(allowFileType)) {allowType = true;break;}}if (!allowType) {return AjaxResult.error("请上传正确的文件格式");}String fileId = UUID.randomUUID().toString();String subFolder = hashBy256(fileId);File destFolder = new File(uploadDir + File.separator + subFolder);if (!destFolder.exists()) {destFolder.mkdirs();}String originalFilename = file.getOriginalFilename();String fileExt = getFileType(originalFilename);String destFileName = fileId + "." + fileExt;File destFile = new File(uploadDir + File.separator + subFolder + File.separator + destFileName);log.info("file saved in: {}", destFile.getAbsoluteFile());file.transferTo(destFile);String filePath = visitPath + File.separator + subFolder + File.separator + destFileName;String fileUri = transferPathAsImageUri(filePath);Long fileSize = file.getSize();SysFile sysFile = SysFile.builder().fileId(fileId).filePath(filePath).fileFormat(fileExt).fileSize(fileSize).mediaType(contentType).originalName(originalFilename).build();sysFileService.save(sysFile);return AjaxResult.success().put("fileId", fileId).put("filePath", filePath).put("originFileName", originalFilename).put("fileName", destFileName).put("fileUri", fileUri);}private String getFileType(String originalFilename){int extPos = originalFilename.lastIndexOf(".");if (extPos != -1) {return originalFilename.substring(extPos + 1);}throw new RuntimeException("未知类型");}public static String hashBy256(String str) {String s = Integer.toHexString(Math.abs(str.hashCode()) % 256).toUpperCase();if (s.length() == 1) {s = "0" + s;}return s;}public static String transferPathAsImageUri(String fileServerPath) {if (!StringUtils.hasLength(fileServerPath)) {return null;}return "/" + fileServerPath.replaceAll("\\\\", "/");}
}
拦截器
ResourceConfig，该拦截器用于上传后回写到界面
@Configuration
public class ResourceConfig implements WebMvcConfigurer {@Value("${file.visit.path:upload}")private String visitPath;@Value("${file.upload.dir}")private String resourceDir;@Overridepublic void addResourceHandlers(ResourceHandlerRegistry registry) {registry.addResourceHandler("/" + visitPath + "/**").addResourceLocations("file:" + resourceDir + "/");}
}
测试结果展示
前端界面
