Parse array to change $key and add new $value => $key - php

Question

I have such array:
array:8 [
"text" => "rt_field"
"title" => "rt_field"
"type_id" => "rt_attr_uint"
"author_id" => "rt_attr_uint"
"created_at" => "rt_attr_timestamp"
"recommended_at" => "rt_attr_timestamp"
"deleted_at" => "rt_attr_timestamp"
"feeds" => "rt_attr_multi"
]
I need to get this:
array:10 [
"text" => "rt_attr_string"
"text_txt" => "rt_field"
"title" => "rt_attr_string"
"title_txt" => "rt_field"
"type_id" => "rt_attr_uint"
"author_id" => "rt_attr_uint"
"created_at" => "rt_attr_timestamp"
"recommended_at" => "rt_attr_timestamp"
"deleted_at" => "rt_attr_timestamp"
"feeds" => "rt_attr_multi"
]
I try parse array ($key => $value). When $value == rt_field: I try rename $key to $key.'_txt', and add such key as default (without _txt) with $value = rt_attr_string.
My code:
foreach ($array_param as $key => $value) {
if ($value == 'rt_field'){
$array_param_second[$key] = 'rt_attr_string';
$array_param[$key] = $key.'_txt';
}
}
$result = array_merge($array_param, $array_param_second);
return $result;
But $key in first array doesn't edit.
What I do wrong?

Answer 1

You are editing the value in either array. If you want to update a key, you need to create a new key.
You can just add the keys to a new array, this way there is no need for merging after the foreach.
$result = [];
foreach ($array_param as $key => $value) {
if ($value == 'rt_field'){
$result[$key] = 'rt_attr_string';
$result[$key . '_txt'] = $value;
} else {
$result[$key] = $value;
}
}

Answer 2

Here is your solution....
Your Array
$array[] = array(
"text" => "rt_field",
"title" => "rt_field",
"type_id" => "rt_attr_uint",
"author_id" => "rt_attr_uint",
"created_at" => "rt_attr_timestamp",
"recommended_at" => "rt_attr_timestamp",
"deleted_at" => "rt_attr_timestamp",
"feeds" => "rt_attr_multi"
);
Solution
$new = array();
$keys = array_keys($array[0]);
foreach($array as $r){
for($i=0;$i<count($keys);$i++){
$key = $keys[$i];
if($r[$key]=='rt_field'){
$new[$key.'_txt'] = $r[$key];
$new[$key] = 'rt_attr_string';
}
else $new[$i][$key] = $r[$key];
}
}
echo "<pre>";print_r($new);