Check if an element is present in an array [duplicate]

by

ECMAScript 2016 incorporates an includes() method for arrays that specifically solves the problem, and so is now the preferred method.

[1, 2, 3].includes(2);     // true
[1, 2, 3].includes(4);     // false
[1, 2, 3].includes(1, 2);  // false (second parameter is the index position in this array at which to begin searching)

As of JULY 2018, this has been implemented in almost all major browsers, if you need to support an older browser a polyfill is available.

Edit: Note that this returns false if the item in the array is an object. This is because similar objects are two different objects in JavaScript.

More Related Contents:

  1. Creating a JavaScript global array with static elements?
  2. Array.prototype.fill() with object passes reference and not new instance
  3. Why can I add named properties to an array as if it were an object?
  4. Is the order of elements in a JSON list preserved?
  5. Get all unique values in a JavaScript array (remove duplicates)
  6. Find object by id in an array of JavaScript objects
  7. How to get first N number of elements from an array
  8. Merge multiple objects inside the same array into one object [duplicate]
  9. javascript search array of arrays
  10. How do I zip two arrays in JavaScript?
  11. Create copy of multi-dimensional array, not reference – JavaScript
  12. Generate unique number within range (0 – X), keeping a history to prevent duplicates
  13. Javascript Array of Functions
  14. How can you sort an array without mutating the original array?
  15. Array Like Objects in Javascript
  16. Why does changing one array alters the other?
  17. Group by array and add field and sub array in main array
  18. Length of a JavaScript associative array
  19. Perform .join on value in array of objects
  20. JavaScript Array: get “range” of items
  21. Create a reset of javascript Array prototype when Array.prototype has been modified?
  22. Deep comparison of objects/arrays [duplicate]
  23. How to check if an array contains another array?
  24. Javascript recursive array flattening
  25. Remove duplicate objects from an array using javascript
  26. How can I use optional chaining with arrays and functions?
  27. How to remove duplicates from a two-dimensional array? [closed]
  28. Javascript – sorting array by multiple criteria
  29. Group javascript array object by same key
  30. Converting Array of Objects into Array of Arrays

Leave a Comment