code: func (menu *Menu) AddConditional(buttons []*Button, matchRule *MatchRule) error {
  	accessToken, err := menu.GetAccessToken()
  	if err != nil {
  		return err
  	}
  
  	uri := fmt.Sprintf("%s?access_token=%s", menuAddConditionalURL, accessToken)
  	reqMenu := &reqMenu{
  		Button:    buttons,
  		MatchRule: matchRule,
  	}
  
  	response, err := util.PostJSON(uri, reqMenu)
  	if err != nil {
  		return err
  	}
  
  	return util.DecodeWithCommonError(response, "AddConditional")
  }
docs: //AddConditional 添加个性化菜单