array_search() DOES NOT check anything in position 0

[sujyrokimora]

Description

The following code:

$array1=['289','290','297'];
$array2=['289','290','297'];
$num=0;
while ($num<count($array1))
{
    echo print_r($array1,true);
    echo '<br>';
    echo print_r($array2,true);
    $t=$array1[$num];
    echo '<br>';
    echo  $t;
    echo '<br>';
     if (array_search($t,$array2,TRUE))
     {
         echo 'This matched: '.$array1[$num];
     }
    echo '<br>';
    $num++;
}

Resulted in this output:

Array ( [0] => 289 [1] => 290 [2] => 297 )
Array ( [0] => 289 [1] => 290 [2] => 297 )
289
Array ( [0] => 289 [1] => 290 [2] => 297 )
Array ( [0] => 289 [1] => 290 [2] => 297 )
290
IThis matched: 290
Array ( [0] => 289 [1] => 290 [2] => 297 )
Array ( [0] => 289 [1] => 290 [2] => 297 )
297
This matched: 297

But I expected this output instead:

Array ( [0] => 289 [1] => 290 [2] => 297 )
Array ( [0] => 289 [1] => 290 [2] => 297 )
289
This matched: 289
Array ( [0] => 289 [1] => 290 [2] => 297 )
Array ( [0] => 289 [1] => 290 [2] => 297 )
290
IThis matched: 290
Array ( [0] => 289 [1] => 290 [2] => 297 )
Array ( [0] => 289 [1] => 290 [2] => 297 )
297
This matched: 297

https://3v4l.org/r5tN9#v8.1.7

PHP Version

PHP 8.1.2

Operating System

Windows 10- 10.0.19044 N/A Build 19044

[kallesommernielsen]

This is because you are not comparing the return value against false like the documentation states, so it's not a bug

[sujyrokimora]

Weird when i replace with in_array just works no skipping

[7snovic]

@sujyrokimora this is not a bug, in your example using array_search and in the first iteration, array_search will return the first key which is 0, so checking the return value from the first iteration will be 0, you need to check against its value & type, so something like if (array_search($t,$array2,TRUE) !== false) will fix it.

in_array returns a bool, so by default will return true in each case from your mentioned cases.

[PrinzAI]

Granda Kalle

[sujyrokimora]

@sujyrokimora this is not a bug, in your example using array_search and in the first iteration, array_search will return the first key which is 0, so checking the return value from the first iteration will be 0, you need to check against its value & type, so something like if (array_search($t,$array2,TRUE) !== false) will fix it.

in_array returns a bool, so by default will return true in each case from your mentioned cases.

Oh ok my bad, i did fix it with another solution using in_array also works. I will close the issue.

[damianwadley]

Note that array_search is meant for searching the array for an item and returning the key. If you don't care about knowing the key and just want to know if a value is in the array then in_array is better.