For a more detail understanding, it can be read here. The method returns -1 when there is no matching element. or / therefore node will start looking for the module in the node_modules in a specific order till react is found. The JavaScript Array findIndex () method is used to get the index of the first element that passed the function you specified as its argument.

I want to render Header in root import React, from 'react', this does not start with a. The findIndex () method in JavaScript is used to search an array for an element that matches a specific condition, and returns the index of the first element that matches the condition. This method could be implemented as follows.Ī = function (predicate, thisValue) Īs you can see in Kangax’ ECMAScript 6 compatibility table, recent versions of Firefox and Chrome already support the *() methods.įurthermore, Paul Millr’s es6-shim has backported the methods to ECMAScript 5.I can't believe that I'm asking an obvious question, but I still get the error in console log.Ĭonsole says that it can't find the module in the directory, but I've checked at least 10 times for typos. If the callback never returns true, find() returns undefined (2). It executes the callback function once for every index in the array until it finds the one where callback returns true.

If predicate returns true, find() stops iterating and returns the current element (1). let text ' Hello, WORLD ' let trimmedText im() console.log(trimmedText) // 'Hello, WORLD' Hello, WORLD. The () method returns an index in the array if an element in the array satisfies the provided testing function otherwise, it will return -1, which indicates that no element passed the test. In case no such element is present in the array that satisfies the specified condition. The signature of the callback predicate() isįind() iterates over the array (while skipping holes) and calls predicate for each element. How findIndex () Method Works in JavaScript Array specified in the argument has no elements, that is, if it is an empty array. Two new Array methods (proposed by Rick Waldron) are in the latest ECMAScript 6 specification draft:Ī(predicate, thisValue?) Newer version of this post: “ ECMAScript 6’s new array methods” You can use the function to find index of a particular element as below, var index functiontofindIndexByKeyValue (studentsArray, 'name', 'tanmay') alert (index) Share Follow answered at 12:51 Ravinder Singh Bhanwar 826 8 18 Add a comment 10 Use indexOf imageList.

Findindex in javascript