springmvc采用formdata进行多文件上传 博客分类： spingMVCspringjava
程序员文章站
2024-03-16 19:11:52
...
参考链接：https://www.cnblogs.com/kanyun/p/7159232.html
https://www.cnblogs.com/kanyun/p/7159232.html
因为项目是前后端分离，且跨域访问。采用form表单提交难以实现。故需要引入formdata，采用ajax提交。
一、文件上传
参考地址中已经写的很详细了。这里只做个代码简化
前端代码：
<form enctype="multipart/form-data" id="formfile" class="upload-img"> <input type="file" multiple="multiple" /> </form>
$(document).on("change", ".upload-img input:file", function() {
var t_files = this.files;
var data = new FormData();
for (var i=0;i<t_files.length;i++){
data.append('file',t_files[i]);
}
$.ajax({
url : 'http://localhost:8080/YDplatform/apply/uploadScanFiles', //用于文件上传的服务器端请求地址
type : 'post',
processData: false, // 告诉jQuery不要去处理发送的数据
contentType: false, // 告诉jQuery不要去设置Content-Type请求头
data:data,
cache: false
}).done(function(data,status){
var dataObj = jQuery.parseJSON(data);
if(dataObj.state == -1){
new Message().showMsg("上传图片出错");
}else{
}
}).fail(function (res) {
})
});
后端代码：
@ResponseBody
@RequestMapping(value = "uploadScanFiles", method = RequestMethod.POST)
public HttpResponse uploadScanFiles(HttpServletRequest request,
@RequestParam(value = "file", required = true) List<MultipartFile> files, String key, Long applyId,
Long appId) throws Exception {
if (null == files || 0 == files.size()) {
throw BizException.create(Code.ParamError, "文件为空");
}
for (MultipartFile file : files) {
System.out.println("文件名：" + file.getOriginalFilename() + "---contentType：" + file.getContentType());
}
return HttpResponse.OK();
}
注意：前端formdata的参数名和后台注解@RequestParam的value要对应上。后端接收参数里面除了文件以外，还有其它字段参数，也是可以用formdata来append的，这里就不改动了。
二、文件下载
参考链接：https://blog.csdn.net/a447332241/article/details/78998239
前端代码：
1、ajax的方式
ajax请求无法响应下载功能。因为response原因，一般请求浏览器是会处理服务器输出的response，例如生成png、文件下载等,然而ajax请求只是个“字符型”的请求，即请求的内容是以文本类型存放的。文件的下载是以二进制形式进行的，虽然可以读取到返回的response，但只是读取而已，是无法执行的，说白点就是js无法调用到浏览器的下载处理机制和程序。
推荐使用这种方式 自己构建表单进行提交
var form = $("<form>");
form.attr("style","display:none");
form.attr("target","");
form.attr("method","post");
form.attr("action",rootPath + "T_academic_essay/DownloadZipFile.do");
var input1 = $("<input>");
input1.attr("type","hidden");
input1.attr("name","strZipPath");
input1.attr("value",strZipPath);
$("body").append(form);
form.append(input1);
form.submit();
form.remove();
2、a标签
如果下载没有必要用到ajax的话，a标签是最好的选择。
<a href=“下载地址”>导出</a>
后端代码
后端代码有两种方式，我采用的后者：
方式一：直接贴代码
@RequestMapping("/download")
public String download( String fileName ,String filePath, HttpServletRequest request, HttpServletResponse response){
response.setContentType("text/html;charset=utf-8");
try {
request.setCharacterEncoding("UTF-8");
} catch (UnsupportedEncodingException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
java.io.BufferedInputStream bis = null;
java.io.BufferedOutputStream bos = null;
String downLoadPath = filePath; //注意不同系统的分隔符
// String downLoadPath =filePath.replaceAll("/", "\\\\\\\\"); //replace replaceAll区别 *****
System.out.println(downLoadPath);
try {
long fileLength = new File(downLoadPath).length();
response.setContentType("application/x-msdownload;");
response.setHeader("Content-disposition", "attachment; filename=" + new String(fileName.getBytes("utf-8"), "ISO8859-1"));
response.setHeader("Content-Length", String.valueOf(fileLength));
bis = new BufferedInputStream(new FileInputStream(downLoadPath));
bos = new BufferedOutputStream(response.getOutputStream());
byte[] buff = new byte[2048];
int bytesRead;
while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) {
bos.write(buff, 0, bytesRead);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (bis != null)
try {
bis.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (bos != null)
try {
bos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return null;
}
方式二：利用springmvc提供的ResponseEntity类型,使用它可以很方便地定义返回的HttpHeaders和HttpStatus。
RequestMapping("/download")
public ResponseEntity<byte[]> export(String fileName,String filePath) throws IOException {
HttpHeaders headers = new HttpHeaders();
File file = new File(filePath);
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
headers.setContentDispositionFormData("attachment", fileName);
return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),
headers, HttpStatus.CREATED);
}
如果是多文件下载，则需要进行压缩处理：
参考链接：https://www.cnblogs.com/zeng1994/p/7862288.html文
Controller:
@RequestMapping(value = "downloadPackage", method = RequestMethod.GET)
public void downloadPackage2(HttpServletRequest request, @RequestParam(required = true) String key,
Integer processType, Long applyId, HttpServletResponse response) throws Exception {
String fileDir = applicationService.getPackagefileDirByProcessAndKey(applyId, key, processType);
if (StringUtils.isBlank(fileDir)) {
throw BizException.create(Code.NOTEXIST, "文件没找到！");
}
String rootPath = request.getSession().getServletContext().getRealPath("/");
String tempFileName = rootPath + "/" + UUID.randomUUID().toString().replaceAll("-", "");
File temDir = new File(tempFileName);
if (!temDir.exists()) {
temDir.mkdirs();
}
File resource = new File(fileDir);
FileUtils.copyDirectory(resource, temDir);
response.setContentType("application/zip");
response.setHeader("Content-Disposition",
"attachment; filename=package_" + System.currentTimeMillis() + ".zip");
ZipUtils.toZip(temDir.getPath(), response.getOutputStream(), false);
File[] listFiles = temDir.listFiles();
for (int i = 0; i < listFiles.length; i++) {
listFiles[i].delete();
}
temDir.delete();
}
Utils:
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
/**
*
* ZipUtils
*
* @author ZENG.XIAO.YAN
*
* @date 2017年11月19日 下午7:16:08
*
* @version v1.0
*
*/
public class ZipUtils {
private static final int BUFFER_SIZE = 2 * 1024;
/**
*
* 压缩成ZIP 方法1
*
* @param srcDir
* 压缩文件夹路径
*
* @param out
* 压缩文件输出流
*
* @param KeepDirStructure
* 是否保留原来的目录结构,true:保留目录结构;
*
* false:所有文件跑到压缩包根目录下(注意：不保留目录结构可能会出现同名文件,会压缩失败)
*
* @throws RuntimeException
* 压缩失败会抛出运行时异常
*
*/
public static void toZip(String srcDir, OutputStream out, boolean KeepDirStructure) throws RuntimeException {
long start = System.currentTimeMillis();
ZipOutputStream zos = null;
try {
zos = new ZipOutputStream(out);
File sourceFile = new File(srcDir);
compress(sourceFile, zos, sourceFile.getName(), KeepDirStructure);
long end = System.currentTimeMillis();
System.out.println("压缩完成，耗时：" + (end - start) + " ms");
} catch (Exception e) {
throw new RuntimeException("zip error from ZipUtils", e);
} finally {
if (zos != null) {
try {
zos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/**
*
* 压缩成ZIP 方法2
*
* @param srcFiles
* 需要压缩的文件列表
*
* @param out
* 压缩文件输出流
*
* @throws RuntimeException
* 压缩失败会抛出运行时异常
*
*/
public static void toZip(List<File> srcFiles, OutputStream out) throws RuntimeException {
long start = System.currentTimeMillis();
ZipOutputStream zos = null;
try {
zos = new ZipOutputStream(out);
for (File srcFile : srcFiles) {
byte[] buf = new byte[BUFFER_SIZE];
zos.putNextEntry(new ZipEntry(srcFile.getName()));
int len;
FileInputStream in = new FileInputStream(srcFile);
while ((len = in.read(buf)) != -1) {
zos.write(buf, 0, len);
}
zos.closeEntry();
in.close();
}
long end = System.currentTimeMillis();
System.out.println("压缩完成，耗时：" + (end - start) + " ms");
} catch (Exception e) {
throw new RuntimeException("zip error from ZipUtils", e);
} finally {
if (zos != null) {
try {
zos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/**
*
* 递归压缩方法
*
* @param sourceFile
* 源文件
*
* @param zos
* zip输出流
*
* @param name
* 压缩后的名称
*
* @param KeepDirStructure
* 是否保留原来的目录结构,true:保留目录结构;
*
* false:所有文件跑到压缩包根目录下(注意：不保留目录结构可能会出现同名文件,会压缩失败)
*
* @throws Exception
*
*/
private static void compress(File sourceFile, ZipOutputStream zos, String name,
boolean KeepDirStructure) throws Exception {
byte[] buf = new byte[BUFFER_SIZE];
if (sourceFile.isFile()) {
// 向zip输出流中添加一个zip实体，构造器中name为zip实体的文件的名字
zos.putNextEntry(new ZipEntry(name));
// copy文件到zip输出流中
int len;
FileInputStream in = new FileInputStream(sourceFile);
while ((len = in.read(buf)) != -1) {
zos.write(buf, 0, len);
}
// Complete the entry
zos.closeEntry();
in.close();
} else {
File[] listFiles = sourceFile.listFiles();
if (listFiles == null || listFiles.length == 0) {
// 需要保留原来的文件结构时,需要对空文件夹进行处理
if (KeepDirStructure) {
// 空文件夹的处理
zos.putNextEntry(new ZipEntry(name + "/"));
// 没有文件，不需要文件的copy
zos.closeEntry();
}
} else {
for (File file : listFiles) {
// 判断是否需要保留原来的文件结构
if (KeepDirStructure) {
// 注意：file.getName()前面需要带上父文件夹的名字加一斜杠,
// 不然最后压缩包中就不能保留原来的文件结构,即：所有文件都跑到压缩包根目录下了
compress(file, zos, name + "/" + file.getName(), KeepDirStructure);
} else {
compress(file, zos, file.getName(), KeepDirStructure);
}
}
}
}
}
public static void main(String[] args) throws Exception {
/** 测试压缩方法1 */
FileOutputStream fos1 = new FileOutputStream(new File("c:/mytest01.zip"));
ZipUtils.toZip("D:/log", fos1, true);
/** 测试压缩方法2 */
List<File> fileList = new ArrayList<>();
fileList.add(new File("D:/Java/jdk1.7.0_45_64bit/bin/jar.exe"));
fileList.add(new File("D:/Java/jdk1.7.0_45_64bit/bin/java.exe"));
FileOutputStream fos2 = new FileOutputStream(new File("c:/mytest02.zip"));
ZipUtils.toZip(fileList, fos2);
}
}