PresentationConnection.state - Web APIs 编辑

The state attribute reflects the presentation connection's current state. Depending on the current PresentationConnectionState, the state attribute can hold one of the following values.

connecting: The user agent is attempting to establish a presentation connection with the destination browsing context. This is the initial state when a PresentationConnection object is created.
connected: The presentation connection is established and communication is possible.
closed: The presentation connection has been closed or could not be opened. The connection may be reopened by calling reconnect(). No communication is possible in this state.
terminated: The receiving browsing context has terminated. Any presentation connection to that presentation has also terminated and cannot be reopened. No communication is possible.