Is it possible to retrieve the JSON object from the Fetch API response and access it externally?

Question

Is it possible to retrieve the JSON object from the Fetch API response and access it externally?

Currently, I am facing an issue accessing the variable emoji_map beyond the scope of the then function in my code and I'm unsure how to resolve it.

Below is the relevant snippet of my code:

 if (req) {
    fetch(req).then(function(response) {
        return response.json();
    }).then(function(response) {
    /* Begin observing */
    emoji_map = response.emoji_map;
    console.log(emoji_map);
    });

}

Whenever I attempt to access emoji_map outside the if loop using a console.log(), I cannot retrieve the assigned response value. Could someone assist me with this?

javascript

Answer 1

Answer №1

For a deeper understanding of JavaScript lexical scoping and closures, I recommend checking out the MDN documentation: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Closures.

function initialize() {
  var fruit = "Apple"; // fruit is a local variable created by init
  function displayFruit() { // displayFruit() is the inner function, a closure
    alert(fruit); // accessing the variable declared in the parent function    
  }
  displayFruit();    
}
initialize();
The function initialize() sets up a local variable called fruit and defines an inner function called displayFruit(). This inner function can only be accessed within the body of initialize(). While displayFruit() does not have any local variables of its own, it can make use of the outer function's variables like fruit.

Answer 2

For a deeper understanding of JavaScript lexical scoping and closures, I recommend checking out the MDN documentation: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Closures.

function initialize() {
  var fruit = "Apple"; // fruit is a local variable created by init
  function displayFruit() { // displayFruit() is the inner function, a closure
    alert(fruit); // accessing the variable declared in the parent function    
  }
  displayFruit();    
}
initialize();
The function initialize() sets up a local variable called fruit and defines an inner function called displayFruit(). This inner function can only be accessed within the body of initialize(). While displayFruit() does not have any local variables of its own, it can make use of the outer function's variables like fruit.

Answer 3

Answer №2

Why not declare a global variable outside the fetch statement and store the response in that variable? This way, you can access the response data later on.


          let responseData;          
          if (request) {
            fetch(request).then(function(response) {
               responseData = response.json();
               return response.json();
            }).then(function(response) {
                 /* Begin observing */
                 emojiData = responseData.emoji_map;
                 console.log(emojiData);
             });

          }

     OR 

      fetch('https://example.com/api/data').then(function(response) {
           return //...
        }).then(function(returnedValue) {
         // ...
       }).catch(function(error) {
           // Handle errors here
       });

You can test out the code above or visit this link for more information.

Answer 4

Why not declare a global variable outside the fetch statement and store the response in that variable? This way, you can access the response data later on.


          let responseData;          
          if (request) {
            fetch(request).then(function(response) {
               responseData = response.json();
               return response.json();
            }).then(function(response) {
                 /* Begin observing */
                 emojiData = responseData.emoji_map;
                 console.log(emojiData);
             });

          }

     OR 

      fetch('https://example.com/api/data').then(function(response) {
           return //...
        }).then(function(returnedValue) {
         // ...
       }).catch(function(error) {
           // Handle errors here
       });

You can test out the code above or visit this link for more information.

Is it possible to retrieve the JSON object from the Fetch API response and access it externally?

Answer №1

Answer №2

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Is it possible to retrieve the JSON object from the Fetch API response and access it externally?

Answer №1

Answer №2

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