string(337) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E7%94%B5%E6%A2%AF%E7%9B%91%E6%8E%A7%E4%B8%93%E7%94%A8%E6%97%A0%E7%BA%BF%E5%A5%97%E8%A3%85%E5%8F%91%E5%B0%84%E7%AB%AF%E6%80%8E%E4%B9%88%E7%9F%A5%E9%81%93%E5%A5%BD%E5%9D%8F => Failed to connect to 61.171.74.35 port 38027: Connection refused"
电梯监控专用无线套装发射端怎么知道好坏
