JavaScript Array Functions Cheat Sheet Part 2

  JavaScript Array Functions Cheat Sheet Part 2

find()

find() returns the value of the first element, that matches the test.

Syntax

    arr.find(callback(element[, index[, array]])[, thisArg])

Example

    [1, 10, 5, 6].find(val => val > 5) // 10

findIndex()

findIndex() returns index of the first element, that matches test

Syntax

    arr.findIndex(callback( element[, index[, array]] )[, thisArg])

Example

    [1, 4, 5, 6].findIndex(val => val > 5) // 3

flat()

flat() creates a new array with sub-array elements flattened by specified depth.

Syntax

    const new_array = arr.flat([depth]);

Example

    [1, [2, [3, [4]]]].flat(2) // [ 1, 2, 3, [4] ]

flatMap()

flatMap() creates a new array with sub-array elements flattened by specified depth.

Syntax

    var new_array = arr

    .flatMap(function callback(

        currentValue[, index[, array]]) {

        // return element for new_array

    } [, thisArg])

Example

    [[2], [4], [6], [8]].flatMap(val => val/2) // [ 1, 2, 3, 4 ]

forEach()

forEach() executes provided function once for each array element.

Syntax

    arr.forEach(callback(currentValue [, index [, array]])[, thisArg])

Example

    [1, 2, 3].forEach(

        val => console.log(val)

    ) // 1 // 2 // 3

includes()

includes() determines if array includes a certain value

Syntax

    arr.includes(valueToFind[, fromIndex])

Example

    [ 1, 2, 3 ].includes(3) // true

Thanks for reading .... 👏👏👏

JavaScript Array Functions Cheat Sheet Part 1