TsgcWebSocketHTTPServer › Methods › Ping
Sends a WebSocket ping frame to every connected WebSocket client.
public void Ping(string aText = '');| Name | Type | Description |
|---|---|---|
aText | const string | Optional payload to carry inside the ping frame; pass an empty string to send a ping with no payload. |
Ping iterates the active connection list and sends a WebSocket ping frame to each upgraded client, returning once the frames are handed to the underlying sockets. Plain HTTP/HTTP2 connections are skipped because the WebSocket ping opcode only applies after a successful handshake. It is a convenient way to keep idle connections alive or to probe liveness manually in addition to the automatic HeartBeat mechanism. When the HeartBeat timeout is configured, the server closes any connection that does not answer within the window; without a timeout the call is fire-and-forget and any pong replies are delivered asynchronously through the standard connection events. Exceptions raised while writing are routed to OnException.
oServer.Ping("keepalive");