How to create function that return promise from callback function

This question already has an answer here:

How do I convert an existing callback API to promises? 17 answers

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The idea is not to create and return the promise from inside the callback, but to create it in the outside function (where you can return it) and only resolve the promise from the callback:

myFunction():Promise<any>{
  return new Promise(resolve => {
    libapi.callnetwork(arg1, callback(data){
      resolve(data);
    });
  });
}

or simply

myFunction():Promise<any>{
  return new Promise(resolve => {
    libapi.callnetwork(arg1, resolve);
  });
}

---

香草，抢解析功能

let myFunction = () => {
    let resolve;
    let promise = new Promise(r => resolve = r);
    libapi.callnetwork(arg1, resolve);
    return promise;
};

---

myFunction():Promise<any>{
  let resolveFn = (data) => data;
  libapi.callnetwork(arg1, resolveFn);
  return new Promise(resolveFn);
}

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