changing keys of a multidimensional array - php

Question

I have a multidimensional array as shown below. How do I change the keys that start with "id of"?
Array
(
[0] => Array
(
[id of ten] => 1871
[name] => bob
)
[1] => Array
(
[id of nine hundred thousand] => 12581
[name] => barney
)
)
Normally, you'd do something like:
foreach ( $array as $k=>$v )
{
$array[$k] ['id'] = $array[$k] ['old'];
unset($array[$k]['old']);
}
In my case, the key changes dynamically (there are thousands of keys in my multidimensional array and they are random but they will always start w/ "id of...")
thx!

Answer 1

I'm wondering if this is what you are looking for:
<?php
$array = array(
array(
"id of one" => 434,
"name" => "bob"
),
array(
"id of two" => 9323,
"name" => "ted"
)
);
$c_array = count($array);
for ($i = 0; $i < $c_array; $i++)
{
foreach ($array[$i] as $key => $value)
{
if (substr($key, 0, 5) == 'id of') {
$array[$i][substr($key, 6)] = $value;
unset($array[$i][$key]);
}
}
}
print_r($array);
?>
NOTE: Includes use of substr() instead of strpos(). See Gumbo's comment below.
https://ideone.com/xBV5L
This outputs:
Array
(
[0] => Array
(
[name] => bob
[one] => 434
)
[1] => Array
(
[name] => ted
[two] => 9323
)
)

Answer 2

This solution is very clean. Array_shift, does two things at once: returns first element (which has the id), and deletes it from the array, so you can directly assign it to the $new_array at 'id'
$new_arr=array();
foreach ( $array as $arr)
{
$new_arr[array_shift($arr)] = $arr;
}

Answer 3

If the 'id of' key is always the first element of the array, you can use the following:
foreach ($input as &$value)
{
$value['key'] = reset($value);
$key = key($value);
unset($value[$key]);
}
Otherwise, the following worked for me:
foreach ($input as &$value)
{
foreach ($value as $key=>$el) {
if (substr($key, 0, 5) == 'id of') {
$value['key'] = $el;
unset($value[$key]);
}
}
}
In both cases you can change $value['key'] to whatever you want the new key to be.