MqttSyncClientReadString 方法

public OperateResult<string, string> ReadString(
	string topic,
	string payload,
	Action<long, long> sendProgress = null,
	Action<string, string> handleProgress = null,
	Action<long, long> receiveProgress = null
)

Public Function ReadString ( 
	topic As String,
	payload As String,
	Optional sendProgress As Action(Of Long, Long) = Nothing,
	Optional handleProgress As Action(Of String, String) = Nothing,
	Optional receiveProgress As Action(Of Long, Long) = Nothing
) As OperateResult(Of String, String)

public:
OperateResult<String^, String^>^ ReadString(
	String^ topic, 
	String^ payload, 
	Action<long long, long long>^ sendProgress = nullptr, 
	Action<String^, String^>^ handleProgress = nullptr, 
	Action<long long, long long>^ receiveProgress = nullptr
)

member ReadString : 
        topic : string * 
        payload : string * 
        ?sendProgress : Action<int64, int64> * 
        ?handleProgress : Action<string, string> * 
        ?receiveProgress : Action<int64, int64> 
(* Defaults:
        let _sendProgress = defaultArg sendProgress null
        let _handleProgress = defaultArg handleProgress null
        let _receiveProgress = defaultArg receiveProgress null
*)
-> OperateResult<string, string>