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TTMSMQTTPacket payload

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#1

Hi,

Subscribing to a topic I'm receiving a Json text in the message payload.
In 2.0.0.0 I'm using the OnRawPacketReceived event to get the payload like this:

var
  lJsonText: string;
begin
  if APacket.PacketType = TTMSMQTTPacketType.mtPUBLISH then begin
    lJsonText := APacket.GetPayload(false);
  end;
end;

What does the boolean parameter to GetPayLoad do? The hint in the Delphi IDE says AIncludeAllProperties. Can the payload for a received packet have several properties?

#2

Edit: The code example in the previous post was incorrect. Here's a better example:

var
  lRawBytes: TArray<byte>;
  lJsonText: string;
begin
  if APacket.PacketType = TTMSMQTTPacketType.mtPUBLISH then begin
    lRawBytes := APacket.GetPayload(false);
    lJsonText := TEncoding.UTF8.GetString(lRawBytes);
  end;
end;
#3

Definition is:

function TTMSMQTTConnectPacket.GetPayload(AIncludeAllProperties: boolean): TBytes;

So, when this boolean parameter is true, it will parse the full stream of bytes to extract every property out of it. It can be left false if there is no need to do this and as such, to gain performance.

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