Iterating and displaying data is a very common part of building applications. This doesn't answer the question, it specifically says without an array of objects to parse and the explanation explicitly says that I want to convert a for loop to map for rendering in a React component.

Wondering how to create loops in React? Otherwise, it is ok to use an index for the If for any reason you want to experiment, then you can even use recursion to render a list. JSX is a custom syntax extension to JavaScript which is used for creating markup with React. I'd appreciate a … – Jonathan Miles Feb 11 '18 at 13:30

All Telerik .NET tools and Kendo UI JavaScript components in one package. The docs are using a simple array. Loop through an object inside of the render method? Learn about JSX and how to use methods like the map function to loop inside React JSX and render a list of items.

And that’s it, you’ve mastered the art of iterating & rendering loops in React!

However, there is more you need to know.

Is there anyway to do this? You can The last thing we’ll do is tidy our code up a bit. Learn more about Thomas at Subscribe to be the first to get our expert-written articles and tutorials for developers!Progress collects the Personal Information set out in our You can also ask us not to pass your Personal Information to third parties here: Telerik and Kendo UI are part of Progress product portfolio. Is the problem that I am using an array of objects? You'll need to call it multiple times to iterate through all the nested keys. Help spread the word about this tutorial! Finish reading about looping with components and move on to the next section!

However, remember that JSX will not work directly in browsers and requires a build step to convert JSX markup into When I first started with React, I realized quite early that I did not know how to loop through an array and render a list of items. All Rights Reserved.Progress, Telerik, Ipswitch, and certain product names used herein are trademarks or registered trademarks of Progress Software Corporation and/or one of its subsidiaries or affiliates in the U.S. and/or other countries. The docs are using a simple array. If it is not available, then create one for each item before the list is rendered. See Wondering how to create loops in React?


If you need to display the whole nested object, one option is to use a function to convert each object into a React component and pass it as an array: Now enhanced with:If you have worked with React before, then there is a high probability that you know what JSX is, or have at least heard of it.

Instead, it relies heavily on the Javascript language itself for these common tasks. In other words, how could we iterate over One of the best things about React is that doesn’t require you to learn a myriad of new methods to manipulate & render data. What's Next. So far I've only been able to use Array.prototype.map(function(item , i){}); which is great for arrays, but for looping through an object so far I've not been able to find a solution other than doing stuff before the render method, which is not ideal in some situations.

Using an index as a key in certain situations could lead us into a pitfall and cause bugs. You substituted array for an object which doesn't help answer the question, or add any further value. However, if you check the console log, you will see that there is a warning like, “Warning: Each child in a list should have a unique Thanks to adding keys there are no more warnings in the console.

If you have worked with React before, then there is a high probability that you know what JSX is, or have at least heard of it.

We'll use a `PanResponder` to register presses on an image.

The above two components are equivalent from React’s point of view.

Progress is the leading provider of application development and digital experience technologies.Copyright © 2020, Progress Software Corporation and/or its subsidiaries or affiliates. In Android 10, codenamed Q, Google puts its focus squarely on privacy and security, with a few other new features like a stylish Dark Theme. Remember that React — and since we’re using JSX (thank you programming gods), it would instead look super pretty: Our component is now programmatically listing out Jake, Jon and Thruster!
It might remind you a bit of a templating language, but with JSX you can use the full power of JavaScript.

So, as the rule of thumb, if you have an array that can change, then use a unique id.

He specializes in frontend web technologies including Vue.js, React.js, React Native for mobile applications, along with backend: PHP, Laravel, Python, Flask, Node.js and Express.js. In React (and other frameworks), the most basic way of doing this is hard coding the entries into your HTML (Easy enough!

Learn about JSX and how to use methods like the map function to loop inside React JSX and render a list of items.

I hope that after reading this article you are now more confident with React and know how to use loops in JSX.Thomas Findlay is a web and mobile developer, mentor, technical writer and consultant with almost six years of experience.

Rendering a Component . However, I would not recommend doing that and, in most cases, you should really stick with the As you can see there are quite a few different ways in which you can render a list of items in React.

Thomas has designed and developed websites and mobile applications for individuals and small and large businesses. Function and Class components both have some additional features that we will discuss in the next sections. The most common way of doing that is with the You should see a rendered list. lensPath(fieldPath), value, this.

I'd appreciate a push into the right direction. To really dig deep into React, check out this full day workshop from Kent C Dodds on the fundamentals of react.