我有一个用Swift1.5构建的项目。当我将代码转换为swift3.0时，它开始在下面代码中的每个“if”语句中显示错误:convenienceinit?(userInfo:[NSObject:AnyObject]){guardletstatusString=userInfo[ConnectionMessage.StatusKey]as?Stringelse{returnnil}guardletstatus=ConnectionStatus(string:statusString)else{returnnil}guardletconnectionId=userInfo[Connecti

我有一个用Swift1.5构建的项目。当我将代码转换为swift3.0时，它开始在下面代码中的每个“if”语句中显示错误:convenienceinit?(userInfo:[NSObject:AnyObject]){guardletstatusString=userInfo[ConnectionMessage.StatusKey]as?Stringelse{returnnil}guardletstatus=ConnectionStatus(string:statusString)else{returnnil}guardletconnectionId=userInfo[Connecti