Switch up the key while iterating through a JSON object

Question

Switch up the key while iterating through a JSON object

Can you modify the key while iterating through objects using an external variable? Picture it like this:

var data = [{
    "id": 1,
    "name": "Simon",
    "age": 13
}, {
    "id": 2,
    "name": "Helga",
    "age": 18
}, {
    "id": 3,
    "name": "Tom",
    "age": 27
}, ]

var key = name;

for (var i = 0; i < data.length; i++) {
    var output = data[i].key;
}

However, this currently results in an undefined output. The aim is to create a function that can manage various types of loops.

javascript arrays json for-loop

Answer 1

Answer №1

To access objects in JavaScript, you can use a similar syntax to arrays. Here is an example of the code you need:

var data = [{
    "id": 1,
    "name": "Simon",
    "age": 13
}, {
    "id": 2,
    "name": "Helga",
    "age": 18
}, {
    "id": 3,
    "name": "Tom",
    "age": 27
}]

var key = "name";

for (var i = 0; i < data.length; i++) {
    var output = data[i][key];
}

In regard to the now-deleted previous answer, I suggest avoiding using foreach since it is not compatible with Internet Explorer 8.

Instead, consider using:

var key = "name";

for (var i in data) {
  if(data.hasOwnProperty(i))
  {
    var output = data[i][key];
  }
}

Answer 2

To access objects in JavaScript, you can use a similar syntax to arrays. Here is an example of the code you need:

var data = [{
    "id": 1,
    "name": "Simon",
    "age": 13
}, {
    "id": 2,
    "name": "Helga",
    "age": 18
}, {
    "id": 3,
    "name": "Tom",
    "age": 27
}]

var key = "name";

for (var i = 0; i < data.length; i++) {
    var output = data[i][key];
}

In regard to the now-deleted previous answer, I suggest avoiding using foreach since it is not compatible with Internet Explorer 8.

Instead, consider using:

var key = "name";

for (var i in data) {
  if(data.hasOwnProperty(i))
  {
    var output = data[i][key];
  }
}

Answer 3

Answer №2

A possible solution to your problem could be a function similar to the one below:

function extractValueFromArray(array, value) {
    for (var idx in array) {
        //perform actions using array[idx][value]
    }
}

To use this function, simply call it with the desired parameters like so:

extractValueFromArray(data, "title")

This function is designed to handle the extraction of specific values from an array of objects. It can be customized further according to specific requirements, but I've kept it concise for simplicity.

Answer 4

A possible solution to your problem could be a function similar to the one below:

function extractValueFromArray(array, value) {
    for (var idx in array) {
        //perform actions using array[idx][value]
    }
}

To use this function, simply call it with the desired parameters like so:

extractValueFromArray(data, "title")

This function is designed to handle the extraction of specific values from an array of objects. It can be customized further according to specific requirements, but I've kept it concise for simplicity.

Switch up the key while iterating through a JSON object

Answer №1

Answer №2

Similar questions

Chrome on OSX Mavericks threw a RangeError because the maximum call stack size was exceeded

Modify a property within an object and then emit the entire object as an Observable

Unveiling the Secrets of AJAX Requests with Enigmatic Strings Attached to URLs

Strengthening JavaScript Security

Failure to receive a server response during the AJAX communication

Finding the position of the latest item added to an array

Showing the ng-controller contents post executing AJAX request using the "as" method

Executing script once the DOM has completed loading

Converting numbers to strings based on locale in React Native

Tips for verifying the rendered view post data retrieval from an API in Vue JS

JavaScript encoding and decoding challenges

Uploading files and data in Laravel using Vue.js and Vuetify: A step-by-step guide

The Bootstrap nav-tab functions perfectly on a local server, but unfortunately does not work when hosted remotely

Embracing the Quirks of JSON: A Call for a

Is there a specific method or function that can effectively translate special characters such as into their corresponding representations?

Strange rendering issues when using the react material-ui dialog

Hover over with your mouse to open and close the dropdown menu in React JS

Can someone advise me on how to ensure my function effectively delivers a desired outcome?

Creating a JSON file in Android using Python when it is not already present

Incorporate attributes into object properties in a dynamic manner