求助开发中遇到一个在if语句中发现的问题

if ClientConnMsgList[i].GUID == guid && ClientConnMsgList[i].Conn != nil{ if ClientConnMsgList[i].Conn.WriteMessage(websocket.TextMessage,mc) != nil{ return false } return true } 在第一个if里面报错： panic: runtime error: invalid memory address or nil pointer dereference [signal 0xc0000005 code=0x0 addr=0x0 pc=0x45b1b1] goroutine 12 [running]: controllers.SendMsgClient(0xc042cdc4f0, 0x9, 0xc0438e5680, 0x55, 0x80, 0x0) D:/Mahjongs/go服务器/Gop/GameServer/src/controllers/chatroom.go:240 +0x156 controllers.SendMsgToClient() D:/Mahjongs/go服务器/Gop/GameServer/src/controllers/chatroom.go:226 +0x1c0 created by controllers.init.2 D:/Mahjongs/go服务器/Gop/GameServer/src/controllers/chatroom.go:107 +0x102 问下第一个if里面报错是因为什么原因啊