js array contains All In One

js array contains All In One

includes & contains & has

Array.prototype.contains

"use strict";

/**
 *
 * @author xgqfrms
 * @license MIT
 * @copyright xgqfrms
 * @created 2020-10-01
 * @modified
 *
 * @description Array.prototype.contains
 * @difficulty Easy Medium Hard
 * @complexity O(n)
 * @augments
 * @example
 * @link
 * @solutions
 *
 * @best_solutions
 *
 */

const log = console.log;

Array.prototype.contains = function (key) {
  // log(`\nthis`, this, this.length);
  // for (let item in this) {
  for (let item of this) {
    // log(`item =,`, item);
    // log(`key =`, key);
    // if (item == key) {
    // if (item === key) {
    // type checker Object.prototype.toString()
    // log(`JSON.stringify(item) === JSON.stringify(key)`, JSON.stringify(item) , JSON.stringify(key));
    if (JSON.stringify(item) === JSON.stringify(key)) {
      // break;
      return true;
    } else {
      // continue;
    }
  }
  return false;
}

const arr = [1, "3", {}];

const test = arr.contains("abc");
const test1 = arr.contains("3");
const test2 = arr.contains({});

log(`test =`, test)
log(`test1 =`, test1)
log(`test2 =`, test2)

/*

test = false
test1 = true
test2 = false

*/

/*

test = false
test1 = true
test2 = true

*/

覆盖 prototype 方法

扩展 prototype 方法

contains

https://developer.mozilla.org/en-US/docs/Web/API/Node/contains

https://developer.mozilla.org/en-US/docs/Web/API/DOMTokenList/contains

https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/permissions/contains

css contain

https://developer.mozilla.org/en-US/docs/Web/CSS/contain

/* Keyword values */
contain: none;
contain: strict;
contain: content;
contain: size;
contain: layout;
contain: style;
contain: paint;

/* Multiple keywords */
contain: size paint;
contain: size layout paint;

/* Global values */
contain: inherit;
contain: initial;
contain: unset;

布局优化，性能优化， 重绘重排

https://drafts.csswg.org/css-contain-1/

hasOwnProperty

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty

has

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set

refs

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/includes

https://www.w3schools.com/jsref/jsref_includes_array.asp#:~:text=The includes() method determines,()%20method%20is%20case%20sensitive.

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