Change the index of an array - php

Question

I need help to change the index of an array.
I have this array:
$items = array('items' => array(
0 => array(
'item_id' => 1,
'item_amount' => 100,
),
1 => array(),
));
Now I want to remove the index, based on the value of item_id, but I don't know how to do this.
I've tried to do it as follows, but doesn't work.
foreach($items['items'] as $key) {
$removeIndex = $key['item_id'] == 1;
if($removeIndex) {
unset($removeIndex);
}
}
How can I do this?

Answer 1

You need to use unset like this:
foreach($items['items'] as $index => $key) { // also get the index!
if (!isset($key['item_id'])) continue; // skip
$removeIndex = $key['item_id'] == 1;
if($removeIndex) {
unset($items['items'][$index]['item_id']); // specify path to that entry
}
}
See it run on eval.in.
To unset something in your nested array structure, you need to act on that array itself. unset($removeIndex) does not change the array, because that is a boolean value.
The extra if is there for the case when you don't have an item_id in some sub-array: in that case that iteration of the loop is skipped.
Removing the entire "row"
If your aim is to also remove the sub-array to which the item_id belongs (so including the item_amount and any other value in that sub-array), then just shorten the "path" in the unset statement:
foreach($items['items'] as $index => $key) { // also get the index!
if (!isset($key['item_id'])) continue; // skip
$removeIndex = $key['item_id'] == 1;
if($removeIndex) {
unset($items['items'][$index]); // specify path to that entry
}
}
See it run on eval.in.

Answer 2

You need to call unset($items['items'][0]). For your case it will be something like this:
$id = 1;
$keyToRemove = false;
foreach ($items['items'] as $key => $value) {
if ($value['item_id'] == $id) {
$keyToRemove = $key;
break;
};
}
if ($keyToRemove) {
unset($items['items'][$keyToRemove]);
}

Answer 3

If you want to remove the specific entry 'item_id' in the $items array, you have to refer to it and use both keys, like in:
foreach($items['items'] as $key => $val) {
if (!isset($val['item_id'])) continue;
$removeIndex = $val['item_id'] == 1;
if($removeIndex)
unset($items['items'][$key]);
}
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