Javascript node.js等待尚未生效的承诺

在我的“app.js”中，我有一个异步函数，等待从我导入的connection.js中连接就绪

// On connection to QLab
qlabconn.on('ready', () => {
    console.log('Connected to QLab!');
    let connectionReady = new Promise(resolve => {
        resolve(true)
    });

    (async () => {
        await core.send_message(`/alwaysReply`, {"type" : 'f', "value" : 1})
    })();
});

我不知道如何让app.js在“等待”状态下正常运行。在connection.js中，我无法在“on”函数中添加导出，也无法在on函数之外添加导出

我仍在学习承诺/等待等，因此如果能为我指出正确的方向，我将不胜感激

app.js

var qlabconn = require('./qlab/connection.js');

// Wait for QLab connection, then we'll start the magic!
(async () => {
    console.log('Ready!');
    var qlabConnectionReady = await qlabconn.connectionReady;
    //qlab.cues.x32_mute('1', "OFF");
    console.log(qlabConnectionReady);
})();

connection.js

// On connection to QLab
qlabconn.on('ready', () => {
    console.log('Connected to QLab!');
    let connectionReady = new Promise(resolve => {
        resolve(true)
    });

    (async () => {
        await core.send_message(`/alwaysReply`, {"type" : 'f', "value" : 1})
    })();
});

---

如果需要基于回调的结果获得承诺，那么应该将逻辑封装在新的承诺回调中。例如，在connection.js中：

// return a reference to qlabconn once we have established a connection
module.exports = function getConnection() {
  return new Promise((resolve, reject) => {
    // let qlabconn = new QLabConnection(...)
    qlabconn.on('ready', () => resolve(qlabconn));
  })
}

然后，我们可以在app.js中正常使用连接对象

const getConnection = require('./connection');

(async () => {
  let qlabconn = await getConnection();
  console.log(qlabconn.connectionReady);

  await core.send_message(`/alwaysReply`, {type: 'f', value: 1});
  console.log('Connected to QLab!');
  // qlab.cues.x32_mute('1', 'OFF');
})();

---

在你的app.js中，

qlabconn.connectionReady

不是没有定义吗？承诺的全部意义在于你可以承诺一些还不可用的东西。另请参阅