Meaning of a port "state" vs "connection"

[qm210]

Hey again,

I got another question that I couldn't figure out from the official docs. Sorry if I was just unable to find. I tried.

What seems to be the difference between port.connection (pending / open / closed) and port.state (connected / disconnected)?

In order to know "I can send notes to that output", does one check for both properties (connection == "open" && state == "connected") or is one of these sufficient?

best,
qm210

[djipco]

Both port.connection and port.state are properties of the MIDIPort object defined by the lower-level Web MIDI API. They are simply exposed by WEBMIDI.js for convenience.

The port.connection property represents the connection state of the device (open, close or pending). It is of type MIDIPortConnectionState. When WEBMIDI.js starts, all ports are automatically opened. So, you really shouldn't worry about opening (or closing) ports. You can listen to the opened event if you wish.

The port.state property represents the state of the device (connected or disconnected). It is of little use since a disconnected port will not even be accessible.