Home > SYS_WebSocket > register

SYS_WebSocket.register() method

Register a WebSocket connection

Signature

function register(
	id: string,
	serviceUri: string,
	receiveMessageCallFn?: (event: MessageEvent<any>) => void | Promise<void>,
	connectedCallFn?: () => void | Promise<void>,
	protocols?: string | Array<string>,
): void;

Parameters

Parameter	Type	Description
id	string	Custom WebSocket ID
serviceUri	string	WebSocket service URI
receiveMessageCallFn	(event: MessageEvent<any>) => void | Promise<void>	(Optional) Callback function when a message is received
connectedCallFn	() => void | Promise<void>	(Optional) Callback function when the connection is established
protocols	string | Array<string>	(Optional) Sub-protocols

Returns

void

Remarks

It can be used to detect whether the WebSocket connection is normal before execution, but note that **do not attempt connections with the same ID but different parameters**, as this will cause confusion: if a WebSocket connection with the specified ID is active, changes to other parameters will not be applied

Note: This API requires the user to enable the extension external interaction permission, if not enabled, it will always throw Error

Example

// 1. 注册连接，挂上「连接成功」与「收到消息」两个回调
eda.sys_WebSocket.register('嘉立创示例_注册', 'ws://127.0.0.1:49620', (event) => {
	// 服务器推送的每条消息都会进入这个回调（event.data 是消息内容）
	console.log('收到服务器消息：', event.data);
}, () => {
	console.log('连接已建立');
});

// 2. register 是同步调用，只登记意图，握手需要一点时间，等待回调触发
await new Promise(r => setTimeout(r, 1500));

// 3. 演示完毕后关闭连接，避免残留
eda.sys_WebSocket.close('嘉立创示例_注册');
console.log('已关闭连接');