WebSocket

open class WebSocket(val url: String, val protocol: String = definedExternally) : EventTarget(source)

The WebSocket object provides the API for creating and managing a WebSocket connection to a server, as well as for sending and receiving data on the connection.

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Constructors

WebSocket

constructor(url: String, protocol: String = definedExternally)

constructor(url: URL, protocol: String = definedExternally)

constructor(url: String, protocols: ReadonlyArray<JsString>)

constructor(url: URL, protocols: ReadonlyArray<JsString>)

Types

Companion

object Companion

ReadyState

sealed interface ReadyState

Properties

binaryType

var binaryType: BinaryType

The WebSocket.binaryType property controls the type of binary data being received over the WebSocket connection.

bufferedAmount

val bufferedAmount: UInt53

The WebSocket.bufferedAmount read-only property returns the number of bytes of data that have been queued using calls to send() but not yet transmitted to the network. This value resets to zero once all queued data has been sent. This value does not reset to zero when the connection is closed; if you keep calling send(), this will continue to climb.

CLOSED

val CLOSED: WebSocket.ReadyState

CLOSING

val CLOSING: WebSocket.ReadyState

CONNECTING

val CONNECTING: WebSocket.ReadyState

extensions

val extensions: String

The WebSocket.extensions read-only property returns the extensions selected by the server. This is currently only the empty string or a list of extensions as negotiated by the connection.

onclose

var onclose: EventHandler<CloseEvent, WebSocket, WebSocket>?

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onerror

var onerror: EventHandler<Event, WebSocket, WebSocket>?

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onmessage

var onmessage: EventHandler<MessageEvent<*>, WebSocket, WebSocket>?

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onopen

var onopen: EventHandler<Event, WebSocket, WebSocket>?

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OPEN

val OPEN: WebSocket.ReadyState

protocol

val protocol: String

The WebSocket.protocol read-only property returns the name of the sub-protocol the server selected; this will be one of the strings specified in the protocols parameter when creating the WebSocket object, or the empty string if no connection is established.

readyState

val readyState: WebSocket.ReadyState

The WebSocket.readyState read-only property returns the current state of the WebSocket connection.

url

val url: String

The WebSocket.url read-only property returns the absolute URL of the WebSocket as resolved by the constructor.

Functions

addEventListener

fun <E : Event> EventTargetLike.addEventListener(type: EventType<E>, handler: (E) -> Unit, options: AddEventListenerOptions? = undefined)

The addEventListener() method of the EventTarget interface sets up a function that will be called whenever the specified event is delivered to the target.

fun close(code: Short = definedExternally, reason: String = definedExternally)

The WebSocket.close() method closes the WebSocket connection or connection attempt, if any. If the connection is already CLOSED, this method does nothing.

dispatchEvent

open fun dispatchEvent(event: Event): Boolean

The dispatchEvent() method of the EventTarget sends an Event to the object, (synchronously) invoking the affected event listeners in the appropriate order.

removeEventListener

fun <E : Event> EventTargetLike.removeEventListener(type: EventType<E>, handler: (E) -> Unit, options: EventListenerOptions? = undefined)

The removeEventListener() method of the EventTarget interface removes an event listener previously registered with EventTarget.addEventListener() from the target.

send

fun send(data: BufferSource)

The WebSocket.send() method enqueues the specified data to be transmitted to the server over the WebSocket connection, increasing the value of bufferedAmount by the number of bytes needed to contain the data. If the data can't be sent (for example, because it needs to be buffered but the buffer is full), the socket is closed automatically. The browser will throw an exception if you call send() when the connection is in the CONNECTING state. If you call send() when the connection is in the CLOSING or CLOSED states, the browser will silently discard the data.

fun send(data: String)

fun send(data: Blob)

when

fun <T : Event> when(type: EventType<T>, options: ObservableEventListenerOptions? = definedExternally): Observable<T>

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