Broadcast Method

Broadcasts a text or stream payload to all connected clients, optionally filtered by channel.

Overloads

Overload 1

Syntax

procedure Broadcast(aMessage: string; aChannel: string = ''; Exclude: String = ''; Include: String = '');

Parameters

Name	Type	Description
`aMessage`	`string`	Text payload wrapped in the sgc envelope and delivered to recipients through OnMessage.
`aChannel`	`string`	Optional channel filter. When supplied, only clients subscribed to that channel receive the payload; leave empty to reach every connection.
`Exclude`	`String`	Semicolon-separated list of connection Guids that must not receive the broadcast.
`Include`	`String`	Semicolon-separated list of connection Guids that the broadcast is restricted to, overriding the channel filter.

Remarks

Text overload. Sends a method=message envelope to the selected recipients. When QoS is Level 1 or Level 2 the server stores the message in the pending list and waits for per-connection acknowledgements, resending if necessary; with QoS Level 0 the message is transmitted once without tracking.

Example

oProtocol.Broadcast('hello everyone');
oProtocol.Broadcast('channel update', 'news');

Overload 2

Syntax

procedure Broadcast(aStream: TStream; aChannel: string = ''; Exclude: String = ''; Include: String = ''; aSize: Integer = 0; aStreaming: TwsStreaming = stmNone);

Parameters

Name	Type	Description
`aStream`	`TStream`	Binary payload sent as-is on the WebSocket; recipients receive it through OnBinary.
`aChannel`	`string`	Optional channel filter. When supplied, only clients subscribed to that channel receive the frame.
`Exclude`	`String`	Semicolon-separated list of connection Guids that must not receive the frame.
`Include`	`String`	Semicolon-separated list of connection Guids that the frame is restricted to.
`aSize`	`Integer`	Chunk size in bytes when the payload is fragmented; pass 0 to send the stream as a single frame.
`aStreaming`	`TwsStreaming`	Streaming strategy (`stmNone`, `stmFragmented`, `stmCustom`) used to chop the stream into frames.

Remarks

Binary overload. Dispatches the stream directly to selected recipients without wrapping it in the sgc JSON envelope, so clients see a raw binary frame. Unlike the text overload this path does not use the QoS pending list; delivery is best-effort on the underlying WebSocket transport.

Example

oStream := TFileStream.Create('image.png', fmOpenRead);
try
  oProtocol.Broadcast(oStream, 'news');
finally
  oStream.Free;
end;

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