WebSocket class

Use the WebSocket interface to connect to a WebSocket, and to send and receive data on that WebSocket.

To use a WebSocket in your web app, first create a WebSocket object, passing the WebSocket URL as an argument to the constructor.

var webSocket = new WebSocket('ws://127.0.0.1:1337/ws');

To send data on the WebSocket, use the send method.

if (webSocket != null && webSocket.readyState == WebSocket.OPEN) {
  webSocket.send(data);
} else {
  print('WebSocket not connected, message $data not sent');
}

To receive data on the WebSocket, register a listener for message events.

webSocket.onMessage.listen((MessageEvent e) {
  receivedData(e.data);
});

The message event handler receives a MessageEvent object as its sole argument. You can also define open, close, and error handlers, as specified by WebSocketEvents.

For more information, see the WebSockets section of the library tour and Introducing WebSockets, an HTML5Rocks.com tutorial.

Inheritance

Object
EventTarget
WebSocket

Annotations

@SupportedBrowser(SupportedBrowser.CHROME)
@SupportedBrowser(SupportedBrowser.FIREFOX)
@SupportedBrowser(SupportedBrowser.IE, '10')
@SupportedBrowser(SupportedBrowser.SAFARI)
@Unstable()
@Native("WebSocket")

Constructors

WebSocket(String url, [Object? protocols]) factory

Properties

binaryType ↔ String? read / write
bufferedAmount → int? read-only
extensions → String? read-only
hashCode → int read-only, inherited: The hash code for this object. [...]
on → Events read-only, inherited: This is an ease-of-use accessor for event streams which should only be used when an explicit accessor is not available.
onClose → Stream<CloseEvent> read-only: Stream of close events handled by this WebSocket.
onError → Stream<Event> read-only: Stream of error events handled by this WebSocket.
onMessage → Stream<MessageEvent> read-only: Stream of message events handled by this WebSocket.
onOpen → Stream<Event> read-only: Stream of open events handled by this WebSocket.
protocol → String? read-only
readyState → int read-only
runtimeType → Type read-only, inherited: A representation of the runtime type of the object.
url → String? read-only

Methods

addEventListener(String type, EventListener? listener, [bool? useCapture]) → void inherited
close([int? code, String? reason]) → void
dispatchEvent(Event event) → bool inherited
noSuchMethod(Invocation invocation) → dynamic inherited: Invoked when a non-existent method or property is accessed. [...]
removeEventListener(String type, EventListener? listener, [bool? useCapture]) → void inherited
send(dynamic data) → void: Transmit data to the server over this connection. [...]
sendBlob(Blob data) → void @JSName('send'): Transmit data to the server over this connection. [...]
sendByteBuffer(ByteBuffer data) → void @JSName('send'): Transmit data to the server over this connection. [...]
sendString(String data) → void @JSName('send'): Transmit data to the server over this connection. [...]
sendTypedData(TypedData data) → void @JSName('send'): Transmit data to the server over this connection. [...]
toString() → String inherited: A string representation of this object. [...]

Operators

operator ==(Object other) → bool inherited: The equality operator. [...]

Static Properties

supported → bool read-only: Checks if this type is supported on the current platform.

Constants

CLOSED → const int: 3
closeEvent → const EventStreamProvider<CloseEvent>: Static factory designed to expose close events to event handlers that are not necessarily instances of WebSocket. [...]
const EventStreamProvider<CloseEvent>('close')
CLOSING → const int: 2
CONNECTING → const int: 0
errorEvent → const EventStreamProvider<Event>: Static factory designed to expose error events to event handlers that are not necessarily instances of WebSocket. [...]
const EventStreamProvider<Event>('error')
messageEvent → const EventStreamProvider<MessageEvent>: Static factory designed to expose message events to event handlers that are not necessarily instances of WebSocket. [...]
const EventStreamProvider<MessageEvent>('message')
OPEN → const int: 1
openEvent → const EventStreamProvider<Event>: Static factory designed to expose open events to event handlers that are not necessarily instances of WebSocket. [...]
const EventStreamProvider<Event>('open')

© 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
https://api.dart.dev/stable/2.13.0/dart-html/WebSocket-class.html