Remove string from PHP array?

Question

Is it possible to remove a string (see example below) from a PHP array without knowing the index?

Example:

array = array("string1", "string2", "string3", "string4", "string5");

I need to remove string3.

score 44 · Accepted Answer · edited May 23 '17 at 12:10

44

$index = array_search('string3',$array);
if($index !== FALSE){
    unset($array[$index]);
}

if you think your value will be in there more than once try using array_keys with a search value to get all of the indexes. You'll probably want to make sure

EDIT:

Note, that indexes remain unchanged when using unset. If this is an issue, there is a nice answer here that shows how to do this using array_splice.

edited May 23 '17 at 12:10

Community

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answered Nov 08 '10 at 01:13

GWW

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I like this +1 for you. But, how can I confirm that it was removed (display on screen)? – Zac Brown Nov 08 '10 at 01:38
Check out the php functions print_r and var_dump. You can use them to dump the contents of your array. – GWW Nov 08 '10 at 01:39
note that using unset() will keep indexes untouched: http://stackoverflow.com/a/369761/176140 – schellmax Jul 24 '13 at 14:15
`array_values` is easier to use than `array_splice` for cleaning up the indexes. – FluorescentGreen5 Mar 12 '17 at 07:10
You should use `if($index)` instead of `if($index !== FALSE)`, it looks cleaner and still works. EDIT: NEVERMIND, it will not work if the string to be removed if it is on index 0. – FluorescentGreen5 Mar 12 '17 at 07:39

score 7 · Answer 2 · answered Jun 10 '16 at 11:39

7

This is probably not the fastest method, but it's a short and neat one line of code:

$array = array_diff($array, array("string3"))

or if you're using PHP >5.4.0 or higher:

$array = array_diff($array, ["string3"])

answered Jun 10 '16 at 11:39

Mikael Grön

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2
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4

I bench-marked you method against GWW's in a for loop that runs 2.5 million times. Your's completed in 18 seconds (17 seconds when I didn't use variables), whereas GWW's completed in 16 seconds. So `array_diff` is slower as is deals with an array instead of a single string, causing overhead. If only there were a function like `array_diff` but for removing a single string in an array. – FluorescentGreen5 Mar 12 '17 at 07:19
2

@FluorescentGreen5 slower but no that much slower, that's only about 5-10% difference which is not worth losing sleep over unless you deal with hundreds of thousands of records, and it might be even less in PHP8 now – Tofandel Mar 15 '22 at 13:01

score 5 · Answer 3 · answered Jun 12 '13 at 13:02

You can do this.

$arr = array("string1", "string2", "string3", "string4", "string5");
$new_arr=array();
foreach($arr as $value)
{
    if($value=="string3")
    {
        continue;
    }
    else
    {
        $new_arr[]=$value;
    }     
}
print_r($new_arr);

score 4 · Answer 4 · answered Sep 19 '15 at 06:00

4

Use a combination of array_search and array_splice.

function array_remove(&$array, $item){
  $index = array_search($item, $array);
  if($index === false)
    return false;
  array_splice($array, $index, 1);
  return true;
}

answered Sep 19 '15 at 06:00

Dustin Poissant

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score 2 · Answer 5 · answered May 17 '19 at 04:32

2

You can also try like this.

$array = ["string1", "string2", "string3", "string4", "string5"];
$key = array_search('string3',$array);
unset($array[$key]);

answered May 17 '19 at 04:32

Sheetal Mehra

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score 1 · Answer 6 · answered Nov 08 '10 at 01:16

It sort of depends how big the array is likely to be, and there's multiple options.

If it's typically quite small, array_diff is likely the fastest consistent solution, as Jorge posted.

Another solution for slightly larger sets:

$data = array_flip($data);
unset($data[$item2remove]);
$data = array_flip($data);

But that's only good if you don't have duplicate items. Depending on your workload it might be advantageous to guarantee uniqueness of items too.

Remove string from PHP array?

6 Answers6