//模型 
     file->extension;//图片的名字只取后缀名        if(empty($text_name)){            $ran=time().rand(10000,99999);//随机名字        }else{
   $ran = $text_name;}        $arr = $arr_type;        if(!empty($arr)){            if(!in_array($fill,$arr)){ return json_encode('格式不正确');}        }        //定义上传大小和类型        if(!empty($siez)){            if($img['size']>$siez) {
   return json_encode('文件大小超过限制');}        }        //文件上传存放的目录        $dir=$dirname.'/'.date("Ymd");        $dir_sev=$name.'/'.date("Ymd");/*数据库存储路径*/        if(!file_exists($dir)) {            mkdir($dir,0777,true);        }        if ($this->validate()) {            //文件名            $fileName = $ran .'.'.$fill;            $dir = $dir."/". $fileName;            if($act == 'update'){
   if($this->file->saveAs($dir)){@unlink($path.$url);}}/*删除图片*/            $uploadSuccessPath = $dir_sev."/". $fileName;/*最后路径*/            return $uploadSuccessPath;        }    }}

//控制器 
     request->isPost) {            $model->file = UploadedFile::getInstance($model, "file");            $file = $model->upload((array)$model->file);            return $file;        }        return $this->render("index", [            "model" => $model,            "uploadSuccessPath" => $uploadSuccessPath,        ]);    }}

//视图 
      ["enctype" => "multipart/form-data"]]);?>            Submit