<"", $width="", $height="")
 {
 // 打开图片的相对路径
 $imgpath = config('img_path');
 // 绝对路径
 $imgRootPath = config('imgRootPath');
 $storeId = '自定义';
 $merchantId = '自定义';
 $old_filename = $storeId . $merchantId . time();
 $filename = $storeId . $merchantId . time() . mt_rand(1000, 9999);
 $type = Goods::upload($whereName, $old_filename);
 if($type) 
 {
  $savepath = $imgRootPath . '/' . $whereName . '/' . $filename . '.' . $type;
  $thumbfile = $filename . '.' . $type;
  $thumbName = $imgpath . '/' . $whereName . '/' . $thumbfile;
  $image = \think\Image::open($imgpath . '/'. $whereName .'/' . $old_filename . '.' . $type);
  $image->thumb($width, $height, \think\Image::THUMB_FIXED)->save($thumbName);
  $data = [
  'access_url' => $imgRootPath . '/' . $whereName . '/' . $filename . '.' . $type,
  'filename' => $thumbfile,
  ];
  return $data;
 }
 } 
}

class Goods
{
 public function upload_sku()
 {
 $whereName = 'goods/sku';
 $width = 750;
 $height = 750;
 $data = Tools::upload_goods_img($whereName,$width, $height);
 return returnJson(1, '上传成功', $data);;
 }
}

//接收上传文件的name
$file = $this->_req->file("upload_head_image");
//将上传的文件移动到public/uploads/user
$info = $file->validate(['size'=>5242880,'ext'=>'jpg,jpeg,png'])->move(ROOT_PATH . 'public' . DS . 'uploads' . DS . 'user');
if($info){
 $pic = new \app\home\model\User();
 $pic_url = $pic->thumbImage($file,$info);
 $user['portrait'] = 'uploads/user/'.$pic_url;
 //print_r($pic_url);exit();
 }

///model中代码如下
 /**
 * [生成用户头像缩略图，180、50]
 * @param [type] $file [获取上传文件$_FILE]
 * @param [type] $pic [上传文件的路径]
 * @return [type] [返回处理后的文件路径]
 */
 public function thumbImage($file,$pic){
 $image = \think\Image::open($file);
 $getSaveName = str_replace('\\','/',$pic->getSaveName());
$portrait_thumbnail_180= 'uploads/user/'.str_replace($pic->getFilename(),'180_'.$pic->getFilename(),$getSaveName);
$image->thumb(180,180,\think\Image::THUMB_CENTER)->save(ROOT_PATH . 'public' . DS . $portrait_thumbnail_180,null,100,true);
 $portrait_thumbnail_80 = 'uploads/user/'.str_replace($pic->getFilename(),'80_'.$pic->getFilename(),$getSaveName);
 $image->thumb(80,80,\think\Image::THUMB_CENTER)->save(ROOT_PATH . 'public' . DS . $portrait_thumbnail_80,null,100,true);
 $portrait_thumbnail_50 = 'uploads/user/'.str_replace($pic->getFilename(),'50_'.$pic->getFilename(),$getSaveName);
 $image->thumb(50,50,\think\Image::THUMB_CENTER)->save(ROOT_PATH . 'public' . DS . $portrait_thumbnail_50,null,100,true);
if ($image) {
  return $getSaveName;
 }
 }