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WebSocket - WebSockets - Web documentation
interface WebSocket
extends EventTarget
allow-net
Private

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

If you are looking to create a WebSocket server, please take a look at Deno.upgradeWebSocket().

Properties

Returns a string that indicates how binary data from the WebSocket object is exposed to scripts:

Can be set, to change how binary data is returned. The default is "blob".

readonly
bufferedAmount: number

Returns the number of bytes of application data (UTF-8 text and binary data) that have been queued using send() but not yet been transmitted to the network.

If the WebSocket connection is closed, this attribute's value will only increase with each call to the send() method. (The number does not reset to zero once the connection closes.)

readonly
extensions: string

Returns the extensions selected by the server, if any.

onclose: ((
this: WebSocket,
) => any) | null
onerror: ((
this: WebSocket,
) => any) | null
onmessage: ((
this: WebSocket,
) => any) | null
onopen: ((
this: WebSocket,
ev: Event,
) => any) | null
readonly
protocol: string

Returns the subprotocol selected by the server, if any. It can be used in conjunction with the array form of the constructor's second argument to perform subprotocol negotiation.

readonly
readyState: number

Returns the state of the WebSocket object's connection. It can have the values described below.

readonly
url: string

Returns the URL that was used to establish the WebSocket connection.

readonly
CLOSED: number
readonly
CLOSING: number
readonly
CONNECTING: number
readonly
OPEN: number

Methods

close(
code?: number,
reason?: string,
): void

Closes the WebSocket connection, optionally using code as the WebSocket connection close code and reason as the WebSocket connection close reason.

send(data:
string
| ArrayBufferLike
| Blob
| ArrayBufferView
): void

Transmits data using the WebSocket connection. data can be a string, a Blob, an ArrayBuffer, or an ArrayBufferView.

addEventListener<K extends keyof WebSocketEventMap>(
type: K,
listener: (
this: WebSocket,
) => any,
options?: boolean | AddEventListenerOptions,
): void
addEventListener(
type: string,
options?: boolean | AddEventListenerOptions,
): void
removeEventListener<K extends keyof WebSocketEventMap>(
type: K,
listener: (
this: WebSocket,
) => any,
options?: boolean | EventListenerOptions,
): void
removeEventListener(
type: string,
options?: boolean | EventListenerOptions,
): void