引入 use think\File;      

public function upload() {        

  $file = request()->file('data');        
  $fileInfo = pathinfo($file);        
  $tmp = $fileInfo['dirname'].'/'.$fileInfo['basename'];        
  $saveName = $file->getOriginalName();        
  $savePath = root_path().'public/storage/';        
  $file = new File($tmp);        
  $file = $file->move($savePath, $saveName);                


  /*$file 是对象，            
    $tmp :  上传缓存地址              
    $savePath: 文件保存地址            
    $saveName: 文件保存名称        
  */  
}