我无法使用此代码保存从简单表单上传的图像
public function actionImage()
{
print_r($_FILES);
$dir = Yii::getPathOfAlias('application.uploads');
if(isset($_POST['img']))
{
$model = new FileUpload();
$model->attributes = $_POST['img'];
$model->image=CUploadedFile::getInstance($model,'image');
if($model->validate())
{
$model->image->saveAs($dir.'/'.$model->image->getName());
// redirect to success page
}
}
}