React is a well-known Javascript library that helps to create User Interfaces and their components. It is an open-source library that is available freely online for everyone to use. It was developed by Facebook in 2011, React is an extremely useful library that lets developers create single-page websites and mobile applications on the browser. It has various distinct benefits, for instance, it provides high data flow, is cross-platform, and follows a component-centric approach while approaching different concerns. Eventually, React started growing and after many enhancements, bug fixes, and documents, it became increasingly stable and in turn popular. Some of the biggest companies like Instagram, Uber Eats, Discord, Skype, etc. use React for their websites and applications. The library has many benefits, and array functions are one of them.
React Array Functions-
- map()-
The map() method is used widely to create React lists. React List is a way to display various kinds of data in an orderly way. Extremely useful in creating the user interfaces of any website, React lists are utilised primarily to show different kinds of menus on any website. The approach of React for the iteration of List is to use native JavaScript. The map() method is an array method where a new array result is returned with the running of a function on the items of an array. New sets of arrays are created without any modifications to the original one.
- reduce()
This array method is widely used on React to reduce the elements present in an array into one. It can’t access the index or the current value of an array and instead just utilises its previous value. Two arguments are accepted to perform an action and the return can be an object, integer, string, or array. The two parameters are called current value and accumulator. The callback function runs one time lesser than the total length of the array.
- includes()
This function is used by developers when they need to check the presence of a particular element in an array. The return value is a boolean, i.e the function checks if the element passed in the parameter is present in the array and returns ‘true’ if it is and ‘false’ if it isn’t. When checking for strings and characters, the function is case-sensitive since javascript is too. When a single argument is passed into the parameter, the function searches the entire array for the element. Whereas, when two arguments are passed, the first one is the element and the second is the index from where to start the search inside the array.
- every()-
An array function of React that is not so well-known, the every() function can be used to check if the elements present in the array adhere to a given condition that is passed in the parameter by the developer. The return value is boolean where if all the elements follow the condition, the return value is a ‘true’ and if not, it’s ‘false’.
Many other array functions are available in-built on React and are utilised for many reasons like React lists need the map() function.