Just remember: only use find when you want a single element returned, and that it returns undefined if nothing is found! Otherwise, use the filter method when you need multiple elements returned. It’s one of several useful methods available on Arrays, for a more complete guide see How To Use Array Methods in JavaScript: Iteration Methods. ConclusionĪrray.find is a simple but incredibly useful method for searching JavaScript arrays. The index is probably not something you’ll need often - but it’s great to have available at times. In non-shorthand, non-ES6 form: const result = trees. Here’s a simple example with an array of strings: const trees = const result = trees.

find (testingFunction ) // that's it! Simple example: Using find() is super easy! The only required parameter of this method is a testing function, and it can be as simple or complex as needed. So if you only need a single value, use find()! When you need to find/return multiple values, reach for filter() instead. Another difference is when nothing is found, this method returns a value of undefined. The function and syntax of find() is very much like the Array.filter method, except it only returns a single element. When you want a single needle from the haystack, reach for find()! When to Use Array.find _.find(characters, 'active').The JavaScript Array.find method is a convenient way to find and return the first occurence of an element in an array, under a defined testing function. Find the first character with a truthy `active` property If not, that means it is a non-digits character and returns false. Step 3 Check if the ASCII value of the character at index i th is between 48 and 57. Step 2 Use the charCodeAt () method to get the ASCII value of the character, which is at the ith index in the string. The find() function operates on a collection, not an array, which means Step 1 Use the for-loop to iterate through the string.

If find() doesn't find an element, it returns undefined. const predicate = v => v > 3 įind() is different from Lodash's filter() function because filter() returns all elements that match a condition, whereas find() returns the first element that matches a condition. `find()` executes `predicate` for every element in the array until // `predicate` returns true. The first element of a collection that matches the given predicate.

Find method javascript