how to delete file using FileSystem in nodeJS?

I dont know why ,but i am not able to delete file using unlink() and unlinksynk().

I have stored file using multiparty.Form() method. It will generate file with random name and returns filePath and originalFileName. And after this i have renamed file with originalFileName.

Code:

      await form.parse(fileData, (err: Error, fields: any, res: any) => {
        if (err) {
          callback(err, null);
        } else {
          let file_path = res.file[0].path;
          let assignedFilePath = file_path.substr(res.file[0].path.lastIndexOf('\/') + 1);
          let originalFilePath = res.file[0].originalFilename;
          originalFilePath = path.dirname(assignedFilePath) + '\\' + originalFilePath;
          fs.rename(assignedFilePath, originalFilePath, function (err: any) {
            if (err)
              callback(err, null);
            else
              callback(err, JSON.stringify({'path': originalFilePath}));
          });
        }
      }); 

Code for deleteFile()

 deleteTempFiles(tempFolderPath: string) {
    return new Promise(function (resolve: any, reject: any) {
      fs.readdir(tempFolderPath, (err: any, files: any) => {
        if (err) {
          reject();
        } else {
          for (let file of files) {
            fs.unlink(tempFolderPath + file, (err: any) => {
              if (err) {
                reject();
              }
            });
          }
          resolve();
        }
      });
    }).catch(function (e) {
      Promise.reject(e.message);
    })
  }

EDIT :

ERROR is, while deleting file ,compiler says Error: EBUSY: resource busy or locked, unlink.

And I think i am not using the file anywhere in program ?

Thanks in advance .

==== 2nd answer ===

Your deleteTempFiles function is utterly wrong read this removing of each file in directory (and directories) inside a dir

You have many logical errors in the code.

1. You use a synchronius for loop, to queue tasks of removing list of files (And directories) from given directory.
2. You unlinks all - even directories . and .. - not possible
3. You ALWAYS resolves after that loop, and rejects after 1st error - but usually that reject should be much after resolve (loop is fast, it only queues io access, not executing the unlinks yet, then resolve is executed).

==== 1st answer ===

You have code for renameFile, which moves file form old name(and location) into new one. Therefore deleting old file would not work at all so you should delete new file.