php – find if an array contains an element

I have an array with just a list of ids, like so:

$my_array = array(
 12, 17, 99, 23

Now I know I could probably do something like:

function in_array($haystack = array(), $needle = NULL)
 foreach($haystack as $id)
  if ($id == $needle)
  {return TRUE;}
  {return FALSE;}

but it seems like there’s probably already a function built. What could I use?

Here is Solutions:

We have many solutions to this problem, But we recommend you to use the first solution because it is tested & true solution that will 100% work for you.

Solution 1

No need to create one, it is already there co-incidentally with the same name you are using: in_array too.


if (in_array('foo', $array)){
  // foo is in the array

Solution 2

It’s called in_array() xD

Solution 3

This might be a trick question. Anyway but how about in_array?

Note: Use and implement solution 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from or, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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