WebSocket class Null safety

A two-way HTTP communication object for client or server applications.

The stream exposes the messages received. A text message will be of type String and a binary message will be of type List<int>.

Implemented types
Available Extensions

Constructors

WebSocket()
WebSocket.fromUpgradedSocket(Socket socket, {String? protocol, bool? serverSide, CompressionOptions compression = CompressionOptions.compressionDefault})
Creates a WebSocket from an already-upgraded socket. [...]
factory

Properties

closeCode int?
The close code set when the WebSocket connection is closed. If there is no close code available this property will be null
read-only
closeReason String?
The close reason set when the WebSocket connection is closed. If there is no close reason available this property will be null
read-only
done Future
Return a future which is completed when the StreamSink is finished. [...]
read-only, inherited
extensions String
The extensions property is initially the empty string. After the WebSocket connection is established this string reflects the extensions used by the server.
read-only
first Future
The first element of this stream. [...]
read-only, inherited
hashCode int
The hash code for this object. [...]
read-only, inherited
isBroadcast bool
Whether this stream is a broadcast stream.
read-only, inherited
isEmpty Future<bool>
Whether this stream contains any elements. [...]
read-only, inherited
last Future
The last element of this stream. [...]
read-only, inherited
length Future<int>
The number of elements in this stream. [...]
read-only, inherited
pingInterval Duration?
The interval between ping signals. [...]
read / write
protocol String?
The protocol property is initially the empty string. After the WebSocket connection is established the value is the subprotocol selected by the server. If no subprotocol is negotiated the value will remain null.
read-only
readyState int
Returns the current state of the connection.
read-only
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
single Future
The single element of this stream. [...]
read-only, inherited

Methods

add(dynamic data) → void
Sends data on the WebSocket connection. The data in data must be either a String, or a List<int> holding bytes.
override
addError(Object error, [StackTrace? stackTrace]) → void
Adds an error to the sink. [...]
inherited
addStream(Stream stream) Future
Sends data from a stream on WebSocket connection. Each data event from stream will be send as a single WebSocket frame. The data from stream must be either Strings, or List<int>s holding bytes.
override
addUtf8Text(List<int> bytes) → void
Sends a text message with the text represented by bytes. [...]
any(bool test(dynamic element)) Future<bool>
Checks whether test accepts any element provided by this stream. [...]
inherited
asBroadcastStream({void onListen(StreamSubscription subscription)?, void onCancel(StreamSubscription subscription)?}) Stream
Returns a multi-subscription stream that produces the same events as this. [...]
inherited
asyncExpand<E>(Stream<E>? convert(dynamic event)) Stream<E>
Transforms each element into a sequence of asynchronous events. [...]
inherited
asyncMap<E>(FutureOr<E> convert(dynamic event)) Stream<E>
Creates a new stream with each data event of this stream asynchronously mapped to a new event. [...]
inherited
cast<R>() Stream<R>
Adapt this stream to be a Stream<R>. [...]
inherited
close([int? code, String? reason]) Future
Closes the WebSocket connection. Set the optional code and reason arguments to send close information to the remote peer. If they are omitted, the peer will see WebSocketStatus.noStatusReceived code with no reason.
override
contains(Object? needle) Future<bool>
Returns whether needle occurs in the elements provided by this stream. [...]
inherited
distinct([bool equals(dynamic previous, dynamic next)?]) Stream
Skips data events if they are equal to the previous data event. [...]
inherited
drain<E>([E? futureValue]) Future<E>
Discards all data on this stream, but signals when it is done or an error occurred. [...]
inherited
elementAt(int index) Future
Returns the value of the indexth data event of this stream. [...]
inherited
every(bool test(dynamic element)) Future<bool>
Checks whether test accepts all elements provided by this stream. [...]
inherited
expand<S>(Iterable<S> convert(dynamic element)) Stream<S>
Transforms each element of this stream into a sequence of elements. [...]
inherited
firstWhere(bool test(dynamic element), {dynamic orElse()?}) Future
Finds the first element of this stream matching test. [...]
inherited
fold<S>(S initialValue, S combine(S previous, dynamic element)) Future<S>
Combines a sequence of values by repeatedly applying combine. [...]
inherited
forEach(void action(dynamic element)) Future
Executes action on each element of this stream. [...]
inherited
handleError(Function onError, {bool test(dynamic error)?}) Stream
Creates a wrapper Stream that intercepts some errors from this stream. [...]
inherited
join([String separator = ""]) Future<String>
Combines the string representation of elements into a single string. [...]
inherited
lastWhere(bool test(dynamic element), {dynamic orElse()?}) Future
Finds the last element in this stream matching test. [...]
inherited
listen(void onData(dynamic event)?, {Function? onError, void onDone()?, bool? cancelOnError}) StreamSubscription
Adds a subscription to this stream. [...]
inherited
map<S>(S convert(dynamic event)) Stream<S>
Transforms each element of this stream into a new stream event. [...]
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
pipe(StreamConsumer streamConsumer) Future
Pipes the events of this stream into streamConsumer. [...]
inherited
reduce(dynamic combine(dynamic previous, dynamic element)) Future
Combines a sequence of values by repeatedly applying combine. [...]
inherited
singleWhere(bool test(dynamic element), {dynamic orElse()?}) Future
Finds the single element in this stream matching test. [...]
inherited
skip(int count) Stream
Skips the first count data events from this stream. [...]
inherited
skipWhile(bool test(dynamic element)) Stream
Skip data events from this stream while they are matched by test. [...]
inherited
take(int count) Stream
Provides at most the first count data events of this stream. [...]
inherited
takeWhile(bool test(dynamic element)) Stream
Forwards data events while test is successful. [...]
inherited
timeout(Duration timeLimit, {void onTimeout(EventSink sink)?}) Stream
Creates a new stream with the same events as this stream. [...]
inherited
toList() Future<List>
Collects all elements of this stream in a List. [...]
inherited
toSet() Future<Set>
Collects the data of this stream in a Set. [...]
inherited
toString() String
A string representation of this object. [...]
inherited
transform<S>(StreamTransformer<dynamic, S> streamTransformer) Stream<S>
Applies streamTransformer to this stream. [...]
inherited
where(bool test(dynamic event)) Stream
Creates a new stream from this stream that discards some elements. [...]
inherited

Operators

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

Static Properties

userAgent String?
Gets the user agent used for WebSocket connections.
read / write

Static Methods

connect(String url, {Iterable<String>? protocols, Map<String, dynamic>? headers, CompressionOptions compression = CompressionOptions.compressionDefault}) Future<WebSocket>
Create a new WebSocket connection. The URL supplied in url must use the scheme ws or wss. [...]

Constants

CLOSED → const int
@Deprecated("Use closed instead")
closed
closed → const int
3
CLOSING → const int
@Deprecated("Use closing instead")
closing
closing → const int
2
CONNECTING → const int
@Deprecated("Use connecting instead")
connecting
connecting → const int
Possible states of the connection.
0
OPEN → const int
@Deprecated("Use open instead")
open
open → const int
1