MqttConnectionOptionsKeepAlivePeriod 属性

设置的参数，最小单位为1s，当超过设置的时间间隔没有发送数据的时候，必须发送PINGREQ报文，否则服务器认定为掉线。
The minimum unit of the set parameter is 1s. When no data is sent beyond the set time interval, the PINGREQ message must be sent, otherwise the server considers it to be offline.

public TimeSpan KeepAlivePeriod { get; set; }

Public Property KeepAlivePeriod As TimeSpan
	Get
	Set

public:
property TimeSpan KeepAlivePeriod {
	TimeSpan get ();
	void set (TimeSpan value);
}

member KeepAlivePeriod : TimeSpan with get, set