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Array MethodsThere are many JavaScript array methods.One of the most useful in React is the .map() array method.The .map() method allows you to run a function on each item in the array, returning a new array as the result.In React, map() can be used to generate lists....
const fruits = ["Apple", "Orange", "Apple", "Mango"]; let position = fruits.lastIndexOf("Apple") + 1; document.getElementById("demo").innerHTML = "Apple is found in position " + position;
Run node in your terminal to test your code: $ cd js-arrayMethods node exercise.js (don't forget to console.log your work) ##Some Helpful Resources: W3 Schools Array methods: http://www.w3schools.com/js/js_array_methods.asp W3 Schools Array reference: http://www.w3schools.com/jsre...
The Mozilla Developer Center has a goodreference covering theArrayclass. W3Schools also summarizesArray‘smethods and propertiesand provides somehandy examplesthat you can try out.
Array MethodsMethodDescription concat() Joins two or more arrays, and returns a copy of the joined arrays copyWithin() Copies array elements within the array, to and from specified positions every() Checks if every element in an array pass a test fill() Fill the elements in an array with ...
If you're using an external library, they also have some built-in methods too 👏 Lodash Checks if value is classified as an Array object. constarray=['🍝','🍜','🍲'];constnotArray='not array';_.isArray(array);// true_.isArray(notArray);// false ...
Array Iteration Methods Browser Support concat()is an ECMAScript1 (JavaScript 1997) feature. It is supported in all browsers: ChromeEdgeFirefoxSafariOperaIE YesYesYesYesYesYes ❮PreviousJavaScript ArrayReferenceNext❯ Track your progress - it's free!
fruitsinstanceofArray// returns true Reference http://www.w3schools.com/js/js_arrays.asp http://www.w3schools.com/js/js_array_methods.asp http://www.w3schools.com/jsref/jsref_filter.asp http://www.w3schools.com/jsref/jsref_find.asp...
fruits instanceof Array // returns true Reference http://www.w3schools.com/js/js_arrays.asp http://www.w3schools.com/js/js_array_methods.asp http://www.w3schools.com/jsref/jsref_filter.asp http://www.w3schools.com/jsref/jsref_find.asp...