Javascript array all any

Js any array

Note: Calling this method on an empty array returns false for any condition! , true if the callback function returns a truthy value for at least one element in the array. Otherwise, false. ,The following example tests whether any element in the array is bigger than 10.,The array some() was called upon.

// Arrow function some((element) => < . >) some((element, index) => < . >) some((element, index, array) => < . >) // Callback function some(callbackFn) some(callbackFn, thisArg) // Inline callback function some(function callbackFn(element) < . >) some(function callbackFn(element, index) < . >) some(function callbackFn(element, index, array)< . >) some(function callbackFn(element, index, array) < . >, thisArg) 

Answer by Kallie McLean

Libraries like underscore.js and lodash provide helper methods like these, if you’re used to Ruby’s collection methods, it might make sense to include them in your project., 1 Thank you, I see now [12,5,8,1,4].some(function(e) < return e >10;>); working! – kangkyu Jan 5 ’16 at 10:01 ,The callback passed to .some() will return true whenever it’s called, so if the iteration mechanism finds an element of the array that’s worthy of inspection, the result will be true.,Please be sure to answer the question. Provide details and share your research!

The JavaScript native .some() method does exactly what you’re looking for:

function isBiggerThan10(element, index, array) < return element >10; > [2, 5, 8, 1, 4].some(isBiggerThan10); // false [12, 5, 8, 1, 4].some(isBiggerThan10); // true 

Answer by Annika Ball

The some() method checks if any of the elements in an array pass a test (provided as a function).,some() executes the function once for each element in the array:,some() does not execute the function for empty array elements.,If it finds an array element where the function returns a true value, some() returns true (and does not check the remaining values)

Definition and Usage

The some() method checks if any of the elements in an array pass a test (provided as a function).

Answer by Melanie Bryan

If you call the some() method on an empty array, the result is always false regardless of any condition. For example:,The condition is implemented via a callback function passed into the some() method.,The Array type provides you with an instance method called some() that allows you to test if an array has at least one element that meets a condition.,In this tutorial, you have learned how to use the JavaScrip Array some() method to test if an array has at least one element that meets a condition.

For example, to check if the following array has at least one element less than 5:

.wp-block-code < border: 0; padding: 0; >.wp-block-code > div < overflow: auto; >.shcb-language < border: 0; clip: rect(1px, 1px, 1px, 1px); -webkit-clip-path: inset(50%); clip-path: inset(50%); height: 1px; margin: -1px; overflow: hidden; padding: 0; position: absolute; width: 1px; word-wrap: normal; word-break: normal; >.hljs < box-sizing: border-box; >.hljs.shcb-code-table < display: table; width: 100%; >.hljs.shcb-code-table > .shcb-loc < color: inherit; display: table-row; width: 100%; >.hljs.shcb-code-table .shcb-loc > span < display: table-cell; >.wp-block-code code.hljs:not(.shcb-wrap-lines) < white-space: pre; >.wp-block-code code.hljs.shcb-wrap-lines < white-space: pre-wrap; >.hljs.shcb-line-numbers < border-spacing: 0; counter-reset: line; >.hljs.shcb-line-numbers > .shcb-loc < counter-increment: line; >.hljs.shcb-line-numbers .shcb-loc > span < padding-left: 0.75em; >.hljs.shcb-line-numbers .shcb-loc::before < border-right: 1px solid #ddd; content: counter(line); display: table-cell; padding: 0 0.75em; text-align: right; -webkit-user-select: none; -moz-user-select: none; -ms-user-select: none; user-select: none; white-space: nowrap; width: 1%; >let marks = [ 4, 5, 7, 9, 10, 3 ];Code language: JavaScript (javascript)

…you typically use a for loop, like this:

let marks = [ 4, 5, 7, 9, 10, 3 ]; let lessThanFive = false; for (let index = 0; index < marks.length; index++) < if (marks[index] < 5) < lessThanFive = true; break; >> console.log(lessThanFive);Code language: JavaScript (javascript)

trueCode language: JavaScript (javascript)

The Array type provides you with an instance method called some() that allows you to test if an array has at least one element that meets a condition.

let marks = [ 4, 5, 7, 9, 10, 3 ]; lessThanFive = marks.some(function(e) < return e < 5; >); console.log(lessThanFive); Code language: JavaScript (javascript)

true Code language: JavaScript (javascript)

Now, the code is shorter. To make it more expressive, you can use the arrow function syntax in ES6:

let marks = [ 4, 5, 7, 9, 10, 3 ]; let lessThanFive = marks.some(e => e < 5); console.log(lessThanFive);Code language: JavaScript (javascript)

The following illustrates the syntax of the some() method:

arrayObject.some(callback[, thisArg]); Code language: CSS (css)

The callback function takes three arguments:

function callback(currentElement [[, currentIndex], array]) < // . >Code language: JavaScript (javascript)

The following exists() function uses the some() method to check if a value exists in an array:

function exists(value, array) < return array.some(e =>e === value); > let marks = [4, 5, 7, 9, 10, 2]; console.log(exists(4, marks)); console.log(exists(11, marks)); Code language: JavaScript (javascript)

true falseCode language: JavaScript (javascript)

The following example shows how to check if any number in the marks array is in the range of (8, 10):

let marks = [4, 5, 7, 9, 10, 2]; const range = < min: 8, max: 10 >; let result = marks.some(function (e) < return e >= this.min && e , range); console.log(result); Code language: JavaScript (javascript)

trueCode language: JavaScript (javascript)

If you call the some() method on an empty array, the result is always false regardless of any condition. For example:

let result = [].some(e => e > 0); console.log(result); result = [].some(e => e 

false falseCode language: JavaScript (javascript)

const isAnyArray = require('is-any-array'); isAnyArray(1); // false isAnyArray('ab'); // false isAnyArray(< a: 1 >); // false isAnyArray([1, 2, 3]); // true isAnyArray(new Uint16Array(2))) // true;

var = [element0, element1, element2. elementN]; 

const array = ['?', '?', '?']; // Modern Browser array.includes('?'); // true // Older Browser array.indexOf('?') !== -1; // true 

let arr = ["I", "go", "home"]; delete arr[1]; // remove "go" alert( arr[1] ); // undefined // now arr = ["I", , "home"]; alert( arr.length ); // 3

some(callbackFn) some(callbackFn, thisArg) 

Parameters

A function to execute for each element in the array. It should return a truthy value to indicate the element passes the test, and a falsy value otherwise. The function is called with the following arguments:

The current element being processed in the array.

The index of the current element being processed in the array.

The array some() was called upon.

A value to use as this when executing callbackFn . See iterative methods.

Return value

true if the callback function returns a truthy value for at least one element in the array. Otherwise, false .

Description

The some() method is an iterative method. It calls a provided callbackFn function once for each element in an array, until the callbackFn returns a truthy value. If such an element is found, some() immediately returns true and stops iterating through the array. Otherwise, if callbackFn returns a falsy value for all elements, some() returns false .

some() acts like the "there exists" quantifier in mathematics. In particular, for an empty array, it returns false for any condition.

callbackFn is invoked only for array indexes which have assigned values. It is not invoked for empty slots in sparse arrays.

some() does not mutate the array on which it is called, but the function provided as callbackFn can. Note, however, that the length of the array is saved before the first invocation of callbackFn . Therefore:

• callbackFn will not visit any elements added beyond the array's initial length when the call to some() began.
• Changes to already-visited indexes do not cause callbackFn to be invoked on them again.
• If an existing, yet-unvisited element of the array is changed by callbackFn , its value passed to the callbackFn will be the value at the time that element gets visited. Deleted elements are not visited.

Warning: Concurrent modifications of the kind described above frequently lead to hard-to-understand code and are generally to be avoided (except in special cases).

The some() method is generic. It only expects the this value to have a length property and integer-keyed properties.

Examples

Testing value of array elements

The following example tests whether any element in the array is bigger than 10.

function isBiggerThan10(element, index, array)  return element > 10; > [2, 5, 8, 1, 4].some(isBiggerThan10); // false [12, 5, 8, 1, 4].some(isBiggerThan10); // true 

Testing array elements using arrow functions

Arrow functions provide a shorter syntax for the same test.

[2, 5, 8, 1, 4].some((x) => x > 10); // false [12, 5, 8, 1, 4].some((x) => x > 10); // true 

Checking whether a value exists in an array

To mimic the function of the includes() method, this custom function returns true if the element exists in the array:

const fruits = ["apple", "banana", "mango", "guava"]; function checkAvailability(arr, val)  return arr.some((arrVal) => val === arrVal); > checkAvailability(fruits, "kela"); // false checkAvailability(fruits, "banana"); // true 

Converting any value to Boolean

const TRUTHY_VALUES = [true, "true", 1]; function getBoolean(value)  if (typeof value === "string")  value = value.toLowerCase().trim(); > return TRUTHY_VALUES.some((t) => t === value); > getBoolean(false); // false getBoolean("false"); // false getBoolean(1); // true getBoolean("true"); // true 

Using some() on sparse arrays

some() will not run its predicate on empty slots.

.log([1, , 3].some((x) => x === undefined)); // false console.log([1, , 1].some((x) => x !== 1)); // false console.log([1, undefined, 1].some((x) => x !== 1)); // true 

Calling some() on non-array objects

The some() method reads the length property of this and then accesses each property whose key is a nonnegative integer less than length until they all have been accessed or callbackFn returns true .

const arrayLike =  length: 3, 0: "a", 1: "b", 2: "c", 3: 3, // ignored by some() since length is 3 >; console.log(Array.prototype.some.call(arrayLike, (x) => typeof x === "number")); // false 

Specifications

Browser compatibility

BCD tables only load in the browser

See also

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This page was last modified on Jun 27, 2023 by MDN contributors.

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