EventSource: open event

The open event of the EventSource API is fired when a connection with an event source is opened.

var evtSource = new EventSource('sse.php');

// addEventListener version
evtSource.addEventListener('open', (e) => {
  console.log("The connection has been established.");
});

// onopen version
evtSource.onopen = (e) => {
  console.log("The connection has been established.");
};

• Using server-sent events
• open
• error
• message