how to access variables inside Fetch returned value

Question

I have a products page with a button ( addToCart ) and I use fetch to add the product to req.session.cart on the server. On the front of the app, I use fetch to communicate with the server and get the req.session.cart as a returned value. How to assign the fetch results to an outside variable?

let whatevervariablehere    

function addToCart(e){



  let items = e.target.parentElement.parentElement
   // rest of the clicked item code .....


  //fetch and send the data to server so you can update session
  fetch('sc8', {
  method: 'POST',
  headers: {
  'Accept': 'application/json',
  'Content-type': 'application/json',
  },
  body: JSON.stringify({
  title : title,
  price : price,
  description : description,
  id : id
  })
  }).then(response => response.json()).then((results) => {

//**this is the part I'm talking about**
console.log("|||||results|||||", results)
//**How to get access to "retrievelocalstorage" from outside of this code**
      localstorage = window.localStorage.setItem(JSON.stringify(user), JSON.stringify(results));
      retrievelocalstorage = JSON.parse(window.localStorage.getItem(JSON.stringify(user))) || "No items in cart, Yet!";
       // the below console.log prints the right results
      console.log("retrievelocalstorage", retrievelocalstorage)

      })  //results function end
      .catch(error => console.log(error));



      } //end of addTocart Function



// this prints "outside the addToCart" and nothing else.
// it is outside the addToCart fn and the fetch promise.
// can I have access to retrievelocalstorage value out here, out of the 
//   function and the promise or not?
  **console.log("this is outside the addToCart fn", retrievelocalstorage)**

IS it possible to get access to retrievelocalstorage out side of the results fn?

Edit 1 The console.log("this is outside the addToCart fn", retrievelocalstorage) doesn't print the value of retrievelocalstorage. so the suggestion to add.then(retrievelocalstorage => whatevervariablehere = retrievelocalstorage) is still showing whatevervariable empty in consolelog.

Answer 1

You are in the async context. You should continue working inside the promise:

.then(() => {
   // you can get your data from LocalStorage here
})

The code after fetch works without awaiting results

Or you can wrap async fn to another fn and use async/await

async function() {
  await addToCart...
  // you can get your data from LocalStorage here
}

Answer 2

You can try to use async/await here so that you don't use .then and can assign the result to a variable.

async function getResults() {
  const result = await fetch(...).json() // your code for fetch
  // work with result as a regular variable
}