find element in array javascript
const simpleArray = [3, 5, 7, 15];
const objectArray = [{ name: 'John' }, { name: 'Emma' }]
console.log( simpleArray.find(e => e === 7) )
// expected output 7
console.log( simpleArray.find(e => e === 10) )
// expected output undefined
console.log( objectArray.find(e => e.name === 'John') )
// expected output { name: 'John' }javascript find
const inventory = [
{name: 'apples', quantity: 2},
{name: 'cherries', quantity: 8}
{name: 'bananas', quantity: 0},
{name: 'cherries', quantity: 5}
{name: 'cherries', quantity: 15}
];
const result = inventory.find( ({ name }) => name === 'cherries' );
console.log(result) // { name: 'cherries', quantity: 5 }array find
const array1 = [5, 12, 8, 130, 44];
const found = array1.find(element => element > 10);
console.log(found);
// expected output: 12js array find
var ages = [3, 10, 18, 20];
function checkAdult(age) {
return age >= 18;
}
/* find() runs the input function agenst all array components
till the function returns a value
*/
ages.find(checkAdult);javascript array find
// Use array.find() like this:
var myArrayOfAges = [1,4,6,8,9,13,16,21,53,78];
var result = myArrayOfAges.find(age => age >= 12);
console.log(result); // Output: 13
/* ------ Below is a polyfill from Mozilla: ------ */
// https://tc39.github.io/ecma262/#sec-array.prototype.find
if (!Array.prototype.find) {
Object.defineProperty(Array.prototype, 'find', {
value: function(predicate) {
// 1. Let O be ? ToObject(this value).
if (this == null) {
throw TypeError('"this" is null or not defined');
}
var o = Object(this);
// 2. Let len be ? ToLength(? Get(O, "length")).
var len = o.length >>> 0;
// 3. If IsCallable(predicate) is false, throw a TypeError exception.
if (typeof predicate !== 'function') {
throw TypeError('predicate must be a function');
}
// 4. If thisArg was supplied, let T be thisArg; else let T be undefined.
var thisArg = arguments[1];
// 5. Let k be 0.
var k = 0;
// 6. Repeat, while k < len
while (k < len) {
// a. Let Pk be ! ToString(k).
// b. Let kValue be ? Get(O, Pk).
// c. Let testResult be ToBoolean(? Call(predicate, T, « kValue, k, O »)).
// d. If testResult is true, return kValue.
var kValue = o[k];
if (predicate.call(thisArg, kValue, k, o)) {
return kValue;
}
// e. Increase k by 1.
k++;
}
// 7. Return undefined.
return undefined;
},
configurable: true,
writable: true
});
}Copyright © 2021 Codeinu
Forgot your account's password or having trouble logging into your Account? Don't worry, we'll help you to get back your account. Enter your email address and we'll send you a recovery link to reset your password. If you are experiencing problems resetting your password contact us
