interface CloseEvent implements EventPropertiesreadonlycode: numberReturns the WebSocket connection close code provided by the server. readonlyreason: stringReturns the WebSocket connection close reason provided by the server. readonlywasClean: booleanReturns true if the connection closed cleanly; false otherwise. variable CloseEventtype{ readonly prototype: CloseEvent; new (type: string, eventInitDict?: CloseEventInit): CloseEvent; }