const ws = new WebSocket('ws://127.0.0.1:12705');
ws.onopen = () => {
    console.log('与打印组件建立连接成功: ');
    ws.send(JSON.stringify({
        requestID: '1234',
        command: 'getPrinterList'
    }))
};

ws.onmessage = (e) => {
    const resp = JSON.parse(e.data || '{}')
    if (resp.command === 'getPrinterList') {
        console.log('打印机列表: ', resp.printerList);
    }
};