图片上传时，没有生成文件夹和图片，但是数据库里有图片数据

if(!empty($_POST)){
//1创建对象
$model = D("Profile");
//2编写规则
//3执行验证
if($data = $model->create()){

//判断当前数据表当中是否存在数据
$profile = $model->where('uid=%d',$_GET['id'])->find();

//判断是否有文件上传
if($_FILES['avatar']['error']===0){
//有文件上传
//处理文件上传
//1.加载类
import('ORG.Net.UploadFile');
//2.实例化
$upload = new UploadFile();
//3.指定上传对象的属性
$upload->maxSize = 1024*1024*3;
$upload->savePath = "./public/Uploads/";
$upload->allowTypes = array('image/gif','image/png','image/jpeg','image/wbmp');
$upload->allowExts = array('gif','jpeg','png','bmp','jpg');
$upload->thumb = true;
$upload->thumbMaxWidth = "150,100,50";
$upload->thumbMaxHeight = "150,100,50";
$upload->thumbPrefix = "big_,middle_,small_";
$upload->thumbRemoveOrigin = true;
//4.执行上传
if($upload->upload()){
$info = $upload->getUploadFileInfo();
$data['avatar'] = $info[0]['savename'];
}else{
$this->error($upload->getErrorMsg());
}

}

if(is_null($profile)){
$data['uid'] = $_GET['id'];
$res = $model->add($data);
}else{
$res = $model->where('uid=%d',$_GET['id'])->save($data);
}

if($res){
$this->success('恭喜您，修改成功');
}else{
$this->error('对不起，修改失败');
}
}else{
$this->error($model->getError());
}
//4验证成功执行修改或者报错
}