MqttSubscribeMessageIdentifier 属性

当前的消息的标识符，当质量等级为0的时候，不需要重发以及考虑标识情况
The identifier of the current message, when the quality level is 0, do not need to retransmit and consider the identification situation

public int Identifier { get; set; }

Public Property Identifier As Integer
	Get
	Set

public:
property int Identifier {
	int get ();
	void set (int value);
}

member Identifier : int with get, set