Loop through json object node js. So, what do we do? (In an ES5-enabled environment, you can get an array of the keys of an object from Object. Data from an API is as follows. js? Asked 10 years, 7 months ago Modified 6 years ago Viewed 51k times The data is in a file titled "people. In the example below, I've shown a hard-coded string that contains the JSON, but the JSON string could just as easily have come from a web service or a file. parse (). entries() and some Array prototype methods to filter out null s and properly stringify the result. . loads() function, converting it into a Python dictionary. Remember that V8 (Google's Javascript engine that node. js looping with json Asked 9 years, 2 months ago Modified 7 years, 10 months ago Viewed 53 times I'm trying to get a JSON array of objects with a for loop but for some reason it only works if I pass the index explicitly as a number (e. In this guide, […] How to Loop Through a JSON Array in JavaScript JSON (JavaScript Object Notation) is a lightweight data-interchange format that is often used to transmit data between a web browser and a server. js, we use the forEach method. I need to access the particularly the class-name object I am facing an issue while iterating a JSON data using the . stringify () You can use node-inspector to debug your NodeJS code, set a breakpoint at the beginning of where you want to loop, and inspect the variable you have referring to the object. Here is what ive tried: As I was reading around, I should loop through objects in string array but I could not find similar sample, as the objects are different inside. If I use a variable, which I would This process will typically consist of two steps: decoding the data to a native structure (such as an array or an object), then using one of JavaScript’s in-built methods to loop through that data structure. By following the steps outlined in this tutorial, you can create a function that will loop through any JSON object and access all of its nested data structures. JSON arrays are a type of JSON data structure that can store multiple values of the same type. parse() static method parses a JSON string, constructing the JavaScript value or object described by the string. With the curlcommand, we get the user with Id 3. This tutorial walks you through each of these loops to iterate through an object’s keys and values. Inside the loop, both the key and value of each property can be accessed directly. This method returns an array of [key, value] pairs from the object. js scales well, sometimes better than more heavyweight approaches like Apache. I need some basic insrtuction how to loop through json array in node. Examples 🔗 Recursively print all properties of a JSON object: The client diretory is the one created with "npm init react-app" and also contains the package. It is commonly used for transmitting data in web applications (e. How to iterate over a JSON array in Node. I would look to loop though all blocks (see the image below), nb. The JSON Content looks as below, { "JR": {"James$James. js runs JavaScript code in the Event Loop (initialization and callbacks), and offers a Worker Pool to handle expensive tasks like file I/O. This process will typically consist of two steps: decoding the data to a native structure (such as an array or an object), then using one of JavaScript’s in-built methods to loop through that data structure. stringify (data). I am trying to loop though a JSON object in NODEJS. Now, depending on what it is, is how you will loop. Some solutions to display JavaScript objects are: Displaying the Object Properties by name Displaying the Object Properties in a Loop Displaying the Object using Object. In this tutorial, we will learn how to iterate a JSON array in java with the code and Explanation using json-simple-1. For looping an object we can even use brackets (" []") in the for-in loop property. js application and building the script to call a server API which returns a JSON object, and ultimately iterate through its contents. The forEach method can then be applied to iterate through the array of entries. Looping through JSON object nested properties and displaying them if not null Using Object. I often write recursive functions to find every property of any JSON object, or to search every file in a folder that may have an infinite number of nested subfolders. ---This vi Node. JSON object and add the values to my script, so that my output file will contain all the newly formatted data? This question has been out here a long time, but I wanted to contribute how I usually iterate through a JSON object. keys(). js code to loop through json nested objects Asked 8 years, 6 months ago Modified 8 years, 6 months ago Viewed 960 times Save code snippets in the cloud & organize them into collections. There are a few ways you can do this, one of which is with Object. In this task, we will learn how to convert CSV to JSON using Node. ) Within that loop, you can loop through the array using a standard for loop: I am returning a List<> from a webservice as a List of JSON objects. I know the difference, but many people don't and might be searching for "JSON" rather than "object". sites[0]). We will go through different approaches to Loop through JSON Array and print the data using EJS. Node. But you'd need a shim for older browsers. [Object Object] how JavaScript deals with this situation. json" that is structured as listed below: [{"firstname":"John","lastname":"Smith","age":"40"},{"firstname":"Bill","lastname":"Jones","age":"40"}, ] I'm requesting a JSON API then doing a for each loop over a JSON object and want a way to know once it's complete. To run the file using the command: node index. Looping through a JSON response in JavaScript can be done using various methods, but the most common one is using the ‘for…in’ loop. forEach works well, but when you use a json object, it doesn't work. A good example is tree traversal. We’ll explain the types of loops and how to use them. entries(jsonbody. js Iterate over JSON Array containing JSON Objects Jul 3, 2009 · "How do I iterate over a JSON structure?" You don't. js Strings Streams Date & Time Arrays Promises JSON Iterators Classes Numbers Objects File System Map Process Symbols Platform/OS HTTPS Hashing refine node. Summary Node. values () Displaying the Object using JSON. I had respbody json array in the question. refer to the example section for examples of all approaches. entries method. So basically, I have an array in the format arr = [ {title: " some title", id: "some id"}, {title: " some title2", id: "some id2"}] and all im trying to do is loop through each item in the array and get the value of the ids. Using our Chrome & VS Code extensions you can save code snippets online with just one-click! Its commented out for one. This is my current for each loop Object. com/api/json/v1/1/random. You'll come across it quite often, so in this article, we give you all you need to work Arrays in JSON are almost the same as arrays in JavaScript. The good news is this will work if given an Array of objects as well instead of a nested Object, but only because we don't care about the keys that hold the objects and only that an object actually has a 'car1' property But I need to change that to where it will loop through each element. js) in my back-end codes, and the response. 1. We can't exactly "iterate" through an object like we can an array since it has no defined order. All JSON can be "parsed" into a JS object, but not all JS objects can be "stringified" into JSON. [ { " Explore effective techniques to iterate over JSON data structures in JavaScript, including practical examples and alternative methods. entries () can be used. data. The secret to the scalability of Node. users). If you‘re working with JSON arrays in JS, you‘ll likely need to loop through them and access or manipulate the values they contain. Many questions actually are of the form "how can I access X in this JSON". of block could vary from 0 to10. I think that example can be confuse, because var json is not a JSON object, but an array. CSV (Comma-Separated Values) and JSON (JavaScript Object Notation) are two of the most commonly used data formats in backend development. js is that it uses a small number of threads to handle many clients. Looping through JSON Object Looping can be done in two ways: Looping of an object can be done by using a property for-in loop. This tutorial will guide you on how to loop the array of JSON objects in JavaScript. In JSON, array values must be of type string, number, object, array, boolean or null. js Output: Method 2: Using the fs module: Another approach to read a file in Node JS is by utilizing the fs module. How can I add a loop that will go through each . Hello My fellow programmers, am trying to get Data from this API URL "www. @Marcel: It has to be read as "I have a data nested data structure or JSON, how can I access a specific value?". An optional reviver function can be provided to perform a transformation on the resulting object before it is returned. keys. May 5, 2025 · Master JSON with Node. forEach(([key, JSON is based on the formatting of JavaScript objects, but JSON is just the notation; it is a string of characters representing an object. In this article, I’ll cover both steps, using plenty of runnable examples. Using Standard For Loop: This guide explores all of the options you have for reading and writing JSON files in Node. I could not access the array object from the json file. In this case, . js thanks a lot In this post I’ll guide you through the process of setting up your Node. Closed 10 months ago. keys(yourObject). parse, you can loop through it. CSV is a simple, plain-text format used for storing tabular data, making it the standard for spreadsheet exports and database dumps. I have got a task to iterate through the complex json file that contains json array. You parse it, whereupon you don't have JSON anymore, and you loop through the resulting array. I have a scenario where I am trying to parse through this below json and get all the value of key "name" and key "id" , which I would further store in a variable or array. , sending some data from the server to the client, so it can be displayed on a web page, or vice versa). I am trying to retrieve the value of for example var value = [table][row][0][STATE] or [table][row][1][STATE] or [table][row][2][STATE] but i am How to loop through an array with JSON objects Hi all, Im really struggling with this problem today. I am going to assume that is a typo. How to loop through JSON array? Asked 14 years, 2 months ago Modified 7 years, 4 months ago Viewed 91k times I can't seem to figure out how to parse through the JSON object returned by the jQuery ajax post basically I want to loop through and make a div out of each student returned like so Hi, I get a json object from a webhook. I guess I should use SplitInBatches but despite having seen some example I don’t know how to do it… Is that node is the right to use or there something else to do ? thanks for help. php" by using express (node. The items() method is then applied to the dictionary. js is single-threaded which means your script will block whether you want it or not. Looping through API JSON data in nodejs Asked 3 years, 11 months ago Modified 3 years, 11 months ago Viewed 47 times To do this properly, you would need to iterate through each of your keys in your JSON object. json that has the react-scripts. js Series Overview Node. Albert$string Starting from ECMAScript 2017 you can use the Object. js. In JavaScript, array values can be all of the above, plus any other valid JavaScript expression, including functions, dates, and undefined. To iterate through a JSON object using the items() method, we first load the JSON data using the json. JSON. If you have a JSON object and you want to loop through all of its inner objects, then you first need to get all the keys in an array and loop through the keys to retrieve objects using the key names, like: Take a look at Traverse. In this example, the below Python code employs a recursive function, `iterate_nested_json_recursive`, using a traditional approach with a for loop to traverse through a nested JSON object and print its key-value pairs. g. thecocktaildb. Once you parse the JSON with JSON. We have some JSON test data: The --watchcommand is used to specify the data for the server. js uses) compiles Javascript into machine code which means that most basic operations are really fast and looping through an object with 100 keys would probably take a couple of nanoseconds? Jul 23, 2025 · To access both the keys and values of a JSON object, Object. This loop allows you to access each property in an object. I am trying to use a for loop to iterate through the list and grab the values out of the properties. Learn how to extract specific values from a JSON response in Node. Currently if I use command "npm run build" in the client directory it creates a build without the backend files inside the root folder, and if I use "npm run build" in the root folder it doesn't work because I do not Welcome fellow JavaScript developer! JSON (JavaScript Object Notation) arrays provide a very common and flexible way to store and access ordered collections of data in web and server-side applications. What is JSON? How to loop through JSON array in nodejs? Asked 8 years, 4 months ago Modified 8 years, 4 months ago Viewed 3k times To loop through JSON with Node. js by converting string to JSON object and accessing the required data with ease. length return string length not Object length, you can use Object. js, including third-party packages like jsonfile. parseJSON. JavaScript Object Notation (JSON) is a standard text-based format for representing structured data based on JavaScript object syntax. With my answer I am able to parse the respbody json array and able to fetch fields like po_number using node js. node. The JSON. foreach in a Node Js application. jar. js using this comprehensive guide covering parsing, stringify, file operations, and advanced manipulation techniques. The fs module provides the file content as a string, requiring us to convert it into JSON format using the built-in method JSON. If you the JSON is an array of objects, then you can iterate over it using the traditional for loop. Normally I'd just use a foreach loop, but that has been unsuccessful. wxpy, pu8s, xiidr, bce0, 5qyv, ziqz, yo07v, 6dro, vjtp, xgyp,