On the other hand, if we need to read a file that is somewhere on the internet, we should use fetch, handling it as any other link. If the file is locally saved in our computer, we should use require, thinking about the JSON file as another component of our project. To load JSON files, we need to choose between require and fetch, and decide which is better for our case. With that in mind, we have two ways to read the files with JavaScript, allowing us to load the JSON object directly from a local file. json files are text-based, meaning we can open them with any code editor, but even if it's human readable, reading thousands or millions of entries is not a good idea. But, pages such as Google+ allow users to download data in. We may not see this kind of file too often since most of the connections between computers are via an internet connection, so we don't need to save the data in files on hard drives. These files are very useful because the code becomes lighter but still human-readable and editable with any code editor. json extension and are great for storing data in JSON format to be opened by any programming language and only need to be parsed to make it a JS object. Then we can use it as a regular JS object. But with JSON, we know that we can access the data retrieved very quickly, just calling the JSON method parse. If the backend languages don't have the same syntax to write objects as JS, that will become a headache, and the front-end structure should change from app to app. Let's take, for example, a backend that retrieves an API, which has to be formatted to get consumed in the front-end. Having one standardized way to communicate data from another language as a JS object is necessary and makes life easier. It became popular because JS is the principal developer's tool for the front-end. Now that you understand the methods to do it, you can see how to loop through the array of JSON objects. Arrays are written inside square brackets.Objects are written inside curly brackets.The value can be any primitive data type but never a function.In data pairs, the key needs to be a unique double-quoted string.Data pairs have to be separated by a comma.Data has to be in key/value pairs, separated by a colon.JSON objects are structured to become native JavaScript objects without modifying them, so we need to follow a set of rules to validate that the JSON and JavaScript objects are identical. A JSON object is a data interchange format that saves a text version of a javascript object, but we won't execute any logic on it before parsing the string.A JS object is just an unordered collection of key/value pairs, where the value can be whatever native data type we have in JS.In this case, it's the difference between a JSON object and a JS object. Image from private libarary JSON Object VS JS Objectīefore moving on, there are two concepts that we need to have well-differentiated to understand the core concepts of JSON in JavaScript.
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