前后端分离，浏览器上传下载文件

Posted 2021-11-02 js1314

服务器文件浏览器下载：
vue请求：
downloadService(){
  this.$confirm(‘确认要下载吗?‘, ‘提示‘, {
    confirmButtonText: ‘确认‘,
    cancelButtonText: ‘取消‘,
    type: ‘warning‘
  }).then(() => {
    window.open(encodeURI( restoreService.geturl()+
      ‘/asd/dasd?dsad))
    window.close()
  }).catch(() => {
    this.$message({
      type: ‘info‘,
      message: ‘已取消‘
    });
  })

},

 

//后端请求：

public ResponseEntity<byte[]> simpleExport() throws BackupsException {

try {

String filename = path+ name;
FileObject fileObject = new FileObject();
fileObject = buildFileObject(fileObject, filename, name,contentsProj);
return download(fileObject);

} catch (Exception e) {
e.printStackTrace();
msg = "Error:服务备份失败";
msgError = msg;
}

}

public static FileObject buildFileObject(FileObject fileObject, String fileName, String exportFileName,byte[] data) {
FileInputStream is = null;
FileOutputStream out = null;
try {
File file = new File(fileName);
if (file.exists()) {
file.delete();
}
File fileParent = file.getParentFile();
if(!fileParent.exists()){
fileParent.mkdirs();
}
out = new FileOutputStream(file);
out.write(data, 0, data.length);
is = new FileInputStream(new File(fileName));
fileObject.setStream(is);

} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
finally{
if(out != null)
try {
out.close();
} catch (IOException e) {
}
}
fileObject.setId("2");
fileObject.setName(exportFileName);
fileObject.setSize(10000000);
fileObject.setType(".jar");
return fileObject;
}

public static ResponseEntity<byte[]> download(FileObject fo) throws UnsupportedEncodingException, IOException {
return download(fo.getName(), fo.getStream());
}

public static ResponseEntity<byte[]> download(String name, InputStream fis) throws UnsupportedEncodingException, IOException {
HttpHeaders headers = new HttpHeaders();
// String Agent = WebUtils.getRequest().getHeader("User-Agent");
/*if (null != Agent) {
Agent = Agent.toLowerCase();
if (Agent.indexOf("Mozilla") != -1) {
name = new String(name.getBytes(),"iso8859-1");
} else {
name = java.net.URLEncoder.encode(name,"UTF-8");
}
}*/
name = new String(name.replaceAll(" ", "").getBytes("gb2312"),"ISO_8859_1");
headers.setContentDispositionFormData("attachment", name);
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
headers.set("X-fileName", name);
byte[] bytes = input2byte(fis);
return new ResponseEntity<byte[]>(bytes, headers, HttpStatus.OK);
}

public static final byte[] input2byte(InputStream inStream)
throws IOException {
ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
byte[] buff = new byte[100];
int rc = 0;
while ((rc = inStream.read(buff, 0, 100)) > 0) {
swapStream.write(buff, 0, rc);
}
byte[] in2b = swapStream.toByteArray();
// swapStream.close();
return in2b;
}

 

浏览器上传文件到服务器：

vue请求：

uploadFile(params) {
  this.loading = true
  const _file = params.file;
  // const isLt2M = _file.size / 1024 / 1024 < 2;
  // 通过 FormData 对象上传文件
  var formData = new FormData();
  formData.append("file", _file);
  // if (!isLt2M) {
  //   this.$message.error("请上传2M以下的.xlsx文件");
  //   return false;
  // }
  this.$axios.post(restoreService.geturl() +‘/asd/sdf?we‘,formData,{ headers : { ‘Content-type‘:‘multipart/form-data‘}}).then(res => {
    if (res.data.status === ‘200‘) {
                this.$message({
                  type: ‘success‘,
                  message: res.data.message,
                })
              } else {
                this.$message({
                  type: ‘warning‘,
                  message: res.data.message
                })
              }
    this.$refs.upload.clearFiles();
    this.loading = false
            })
      },

//后端请求：

@RequestMapping(value = "/Import", method = RequestMethod.POST)
public BaseResult<BackUpDto> simpleImport(@RequestParam(value = "file") MultipartFile file) throws Exception {
return logBackupRestoreService.simpleImport(file.getInputStream());
}

public BaseResult<BackUpDto> simpleImport(InputStream inputStream) throws BackupsException {
String path = System.getProperty("user.dir");
String fileGuid = UUID.randomUUID().toString();
File file = new File(path + "\\" + fileGuid + ".tmp");
byte[] bytes = null;
try {
bytes = inputStreamToFile(inputStream, file);
} catch (Exception e) {

}

}

public static byte[] inputStreamToFile(InputStream ins, File file) throws Exception{
ByteArrayOutputStream ous = null;
// OutputStream os = null;
try {
// os = new FileOutputStream(file);
ous = new ByteArrayOutputStream();
int bytesRead = 0;
byte[] buffer = new byte[8192];
while ((bytesRead = ins.read(buffer, 0, 8192)) != -1) {
ous.write(buffer, 0, bytesRead);
}
} catch (Exception e) {
// logger.error(e.getMessage(), e);
throw new Exception(e);
}finally{
if(ous != null){
ous.close();
}
if(ins != null){
ins.close();
}

}
return ous.toByteArray();
}