best practice for nesting promises in succession-CodePudding

I currently have a few functions that return promises such as the below:

function action_one(){
    return new Promise((resolve, reject)->{
        ...
    });
}

I want to be able to wait on one before doing the next promise without nesting them. I had searched for some solutions, one being PromiseAll() but it does not seem to do it in order. Another solution was to do the following:

   promise.then(result =>{
       action
   }.then(result =>{
       action
   }.then(result =>{
       action
   }.then(result =>{
       action
   }.then(result =>{ etc.

which I'm not sure works for my issue but it doesn't seem compactable.

what would be best practice in this situation?

Edit:

I'm not sure how to use the .then chain with multiple promises such as:

promise.then(result =>{
       action
   }promise.then(result =>{
       action
   }promise.then(result =>{
       action
   }promise.then(result =>{
       action
   }promise.then(result =>{ etc.

It does not yield the result I expect

CodePudding user response：

I found my solution:

new Promise(function(resolve, reject) {

  setTimeout(() => resolve(1), 1000);

}).then(function(result) {

  alert(result); // 1

  return new Promise((resolve, reject) => { // (*)
    setTimeout(() => resolve(result * 2), 1000);
  });

}).then(function(result) { // (**)

  alert(result); // 2

  return new Promise((resolve, reject) => {
    setTimeout(() => resolve(result * 2), 1000);
  });

}).then(function(result) {

  alert(result); // 4

});

I needed to return the promise to chain them which is why it was not working. Source: https://javascript.info/promise-chaining

CodePudding user response：

How about using async/await so you will have synchronous function