function upd($id){

        //查询被修改商品信息，并展示

        $newsinfo=M('productbase');

        if(!empty($_POST)){

            $newsinfo->create();

           print_r($_FILES);

           echo "<br/>";

           print_r($_FILES['address']); echo "<br/>";

           print_r($_FILES['address']['name']);

         if(!empty($_FILES['address']['name'])){

            //  //上传图片

        $upload = new \Think\Upload(); //实例化上传类

           $upload->maxSize   =     3145728 ; //设置附件上传大小

               $upload->exts      =     array('jpg', 'gif', 'png', 'jpeg'); //设置附件上传类型

                  $upload->autoSub  =  false;

               $upload->savePath  =      './public/product/';  //设置附件上传目录     上传文件

                   $info   =   $upload->upload();

                    if(!$info) { //上传错误提示错误信息

                   $this->error($upload->getError());    }else{ //上传成功

                  $filename= $info['address']['savename'];

                   }

        $newsinfo->address=$filename;

         } 

          $product->time=time();

         $z= $newsinfo->save();

        if($z){

            $this->success("商品修改成功",U('Admin/Product/showlist'));

        }else{

            $this->error("商品修改失败",U("Admin/Product/showlist"));

        }

        }else{

           //获取商品ID对应的栏目名

         $cid=$newsinfo->where('id='.$id)->getField('cid');//对应navclass的id

         $newsnavname=M('navclass')->where('id='.$cid)->getField('name');

          $this->assign('id',$cid);

           $this->assign('newsnavname',$newsnavname);

         //获取navclass中的所有分类名

         $map['url']='Home/List/productlist';

          $productLanmu=M('navclass')->where($map)->select();

         $this->assign('productLanmu',$productLanmu);

          //联表查询出新闻标题和内容

            $info =$newsinfo->where('id='.$id)->find();

        //$info = $Product->find($Product_id);

        $this->assign('info',$info);

        $this -> display();

        }

    }