Suggestion: In the event the failing expression is thought to legally check with something which's occasionally null or lacking, either specify a default benefit like myOptionalVar!在这里必须给安装师傅点个赞！！第一次和师傅预约安装的时候，通过视频师傅发现了油烟机尺寸小了，他主动帮我联系了太平�