I am trying to add a new value to the array (I know it is possible with array_map() but I would like to test it with the array_walk()).
This is the code:
$array = [
[
'id' => 1,
'name' => 'Jesus',
],
[
'id' => 2,
'name' => 'David',
],
];
And I want this output:
$array = [
[
'id' => 1,
'name' => 'Jesus',
'locked' => 0,
],
[
'id' => 2,
'name' => 'David',
'locked' => 0,
],
];
I tried with the following code:
array_walk($array, static function(array $item): array {
$item += ['locked' => 0];
//var_dump($item); // Here the array has the three values.
return $item;
});
// Also I tried the same code but not returning the array, I mean:
array_walk($array, static function(array $item): void {
$item += ['locked' => 0];
//var_dump($item); // Here the array has the three values.
});
Is it possible what I want with an array_walk()?
That would be the solution with an array_map().
$arrayMapped = array_map(static function(array $item): array {
return $item += ['locked' => 0];
}, $array);
var_dump($arrayMapped);
Cheers!
Arrays are passed by value. You need to define the argument by reference using &
array_walk($array, function(array &$item): void {
$item['locked'] = 0;
});
Related
I have a a number of values/IDs that need to be translated to a single ID, what is the recommended method using PHP?
For example, I want IDs 38332, 84371, 37939, 1275 to all translate to ID 1234 and IDs222, 47391, 798 to all translate to ID 1235, etc. .
I'm thinking PHP has something built-in to handle this efficiently?
I'm thinking PHP has something built-in to handle this efficiently?
You can use the standard array as a map, quickly translating one ID to another:
$table[38332]; # int(1234)
depending on how you store your overall translation table, you can create a function that returns the translation from its input:
$table = $translation('I want IDs 38332, 84371, 37939, 1275 to all translate to ID 1234');
$result = $table[1275] ?? null; # int(1234)
Example:
$parseId = static fn(string $i) => (int)trim($i);
$translation = static fn(string $buffer): array
=> preg_match_all('~((?:\d+,\s*)+\d+)\s+to all translate to ID\s*(\d+)~', $buffer, $_, PREG_SET_ORDER)
? array_reduce($_, static fn (array $carry, array $item): array => [
$ids = array_map($parseId, explode(',', $item[1])),
$carry += array_fill_keys($ids, $parseId($item[2])),
$carry,][2], []) : [];
This is pretty easy to accomplish with PHP, here's one way you could do it:
Using this method, you populate the $map array, using the id you want to replace with as the key, and the value being an array of the keys you want to be replaced. It then calculates a simple key => value array based on this to make comparison a lot quicker.
Instead of creating a copy of the data, you could use foreach ($data as &$record)
$data = [
[
'id' => 1,
'foreign_id' => 38332,
'text' => 'a'
],
[
'id' => 2,
'foreign_id' => 84371,
'text' => 'b'
],
[
'id' => 3,
'foreign_id' => 37939,
'text' => 'c'
],
[
'id' => 4,
'foreign_id' => 1275,
'text' => 'd'
],
[
'id' => 5,
'foreign_id' => 222,
'text' => 'e'
],
[
'id' => 5,
'foreign_id' => 47391,
'text' => 'f'
],
[
'id' => 5,
'foreign_id' => 798,
'text' => 'g'
]
];
$map = [
123 => [
38332,
84371,
37939,
1275
],
1235 => [
222,
47391,
798
]
];
// Calculate a map to speed things up later
$map_calc = [];
foreach ($map as $destination_id => $ids) {
foreach ($ids as $id) {
$map_calc[$id] = $destination_id;
}
}
$new_data = [];
foreach ($data as $record) {
if (isset($map_calc[$record['foreign_id']]))
$record['foreign_id'] = $map_calc[$record['foreign_id']];
$new_data[] = $record;
}
var_dump($new_data);
I've a huge problem. Somehow I need to get the variation_id from an array based on a value of a child array:
$array = [
[
'attributes' => [
'attribute_art-der-karte' => 'Rot'
],
'variation_id' => '222'
],
[
'attributes' => [
'attribute_art-der-karte' => 'Green'
],
'variation_id' => '221'
]
];
So in my case I've two things available:
The key attribute_art-der-karte
The value Rot
I found nothing here instead of a sorting. Any idea? Thanks!
Simply loop over the array and return the variation ID when your condition is met (an attribute exists with the given key and the given value):
function findVariationId(array $array, string $attrName, string $attrValue): ?string {
foreach ($array as $entry) {
if (($entry['attributes'][$attrName] ?? null) === $attrValue) {
return $entry['variation_id'];
}
}
return null;
}
Demo
You can also use array filter for this
<?php
$array = [
[
'attributes' => [
'attribute_art-der-karte' => 'Rot'
],
'variation_id' => '222'
],
[
'attributes' => [
'attribute_art-der-karte' => 'Green'
],
'variation_id' => '221'
]
];
function findByAttribute ($arr, $value) {
$result = array_filter($arr, function($elem) use($value){
return $elem['attributes']['attribute_art-der-karte'] == $value;
});
if ($result) {
return array_shift($result)['variation_id'];
}
return '';
}
var_dump(findByAttribute($array, 'Rot')); // gives '222'
var_dump(findByAttribute($array, 'a')); // returns ''
var_dump(findByAttribute($array, 'Green')); // gives 221
An additional option using array_search() and array_column():
<?php
$array = [
['attributes' => ['attribute_art-der-karte' => 'Rot'], 'variation_id' => '222'],
['attributes' => ['attribute_art-der-karte' => 'Green'], 'variation_id' => '221']
];
$key = array_search (
'Rot',
array_column(array_column($array, 'attributes'), 'attribute_art-der-karte')
);
echo "variation_id: ". (($key === false) ? 'Not found' : $array[$key]["variation_id"]);
?>
Output:
variation_id: 222
You can access the element variation_id using foreach
// One way using loops identify the non-array element
foreach($array as $ele){
if(!is_array($ele)){
print_r($ele);
}
}
// Otherway for direct calling
print_r($array['variation_id']);
I have a multidimensional array like this:
[
[
'id' => 1,
'name' => 'John',
'address' => 'Some address 1'
'city' => 'NY'
],
[
'id' => 2,
'name' => 'Jack',
'address' => 'Some address 2'
'city' => 'NY'
]
...
[ ... ]
]
How can I remove elements in all subarrays and only retain the id and name keys with their values?
Would this work?
$result = array_map(function($arr) {
return [
'id' => $arr['id'],
'name' => $arr['name']
];
}, $orig_array);
You want to retain the first two associative elements, so you can make array_slice() calls within array_map(). (Demo)
var_export(
array_map(fn($row) => array_slice($row, 0, 2), $array)
);
Or mapped called of array_intersect_key() against an establish whitelist array. (Demo)
$keep = ['id' => '', 'name' => ''];
var_export(
array_map(
fn($row) => array_intersect_key($row, $keep),
$array
)
)
Or, you could use array destructuring inside of a classic foreach() and make iterated compact() calls. (Demo)
$result = [];
foreach ($array as ['id' => $id, 'name' => $name]) {
$result[] = compact(['id', 'name']);
}
var_export($result);
If you want to edit the same array in place, you can simply iterate over them and unset them.
<?php
$preserve_keys = ['id','name'];
foreach($arr as &$data){
foreach($data as $key => $value){
if(!in_array($key,$preserve_keys)){
unset($data[$key]);
}
}
}
If you want it as a separate result, loop over and add it to the new array.
<?php
$new_result = [];
foreach($arr as $data){
$new_result[] = [
'id' => $data['id'],
'name' => $data['name']
];
}
print_r($new_result);
I have an array as key => value pair such as:
$array = [ 10 => 'Windows', 12 => 'Keyboard', 15 => 'Monitor' ];
What I would like to achieve without using any foreach or loops the following:
$converted = [
0 => [ 'id' => 10, 'name' => 'Windows'],
1 => [ 'id' => 12, 'name' => 'Keyboard'],
2 => [ 'id' => 15, 'name' => 'Monitor']
];
Here they indices in new array doesn't matter. Any tips??
No foreach and no loop, but now there is a closure:
$result = array_map(function ($id, $name) {
return [
'id' => $id,
'name' => $name
];
}, array_keys($array), array_values($array));
Even if there was a PHP function that did this exactly, it would be using a loop internally.
function do_what_ghazanfar_mir_wants(array $array) {
return array_map(function ($id, $name) {
return [
'id' => $id,
'name' => $name
];
}, array_keys($array), array_values($array));
}
And the single liner is:
$result = do_what_ghazanfar_mir_wants($array);
And the foreach approach for comparison:
$res = [];
foreach ($array as $id => $name) {
$res[] = [ 'id' => $id, 'name' => $name ];
}
If you want to keep it really short then array_walk will do it in one line:
array_walk($array, function(&$value, $key) { $value = ['id' => $key, 'name' => $value]; });
See https://3v4l.org/OEohi
But I think a foreach loop is probably going to be a lot more readable.
Do it with array_map(), Just pass the keys array_keys($array) and values $array as the parameter of your array_map()
<?php
$array = [ 10 => 'Windows', 12 => 'Keyboard', 15 => 'Monitor' ];
function map_by_key($m, $n)
{
return(array('id' => $m, 'name'=>$n));
}
$output = array_map("map_by_key", array_keys($array),$array);
print '<pre>';
print_r($output);
print '</pre>';
?>
DEMO: https://3v4l.org/iTVSm
I have an array:
<?php
$array = [
'fruits' => [
'apple' => 'value',
'orange' => 'value'
],
'vegetables' => [
'onion' => 'value',
'carrot' => 'value'
];
I also have a string:
$string = 'fruits[orange]';
Is there any way to check if the - array key specified in the string - exists in the array?
For example:
<?php
if(array_key_exists($string, $array))
{
echo 'Orange exists';
}
Try this one. Here we are using foreach and isset function.
Note: This solution will also work for more deeper levels Ex: fruits[orange][x][y]
Try this code snippet here
<?php
ini_set('display_errors', 1);
$array = [
'fruits' => [
'apple' => 'value',
'orange' => 'value'
],
'vegetables' => [
'onion' => 'value',
'carrot' => 'value'
]
];
$string = 'fruits[orange]';
$keys=preg_split("/\[|\]/", $string, -1, PREG_SPLIT_NO_EMPTY);
echo nestedIsset($array,$keys);
function nestedIsset($array,$keys)
{
foreach($keys as $key)
{
if(array_key_exists($key,$array))://checking for a key
$array=$array[$key];
else:
return false;//returning false if any of the key is not set
endif;
}
return true;//returning true as all are set.
}
It would be a lot easier to check the other way around. As in check if the key is in the string. Since keys are unique, there's no way you have duplicates.
$array = [
'fruits' => [
'apple' => 'value',
'orange' => 'value'
],
'vegetables' => [
'onion' => 'value',
'carrot' => 'value'
]
];
$string = 'fruits[orange]';
$keys = array_keys($array['fruits']);
foreach($keys as $fruit) {
if(false !== stripos($string, $fruit)) {
return true;
}
}
While this solution is not necessarily ideal, the problem to begin with isn't exactly common.
You can walk recursively:
$array = [
'fruits' => [
'apple' => 'value',
'orange' => 'value'
],
'vegetables' => [
'onion' => 'value',
'carrot' => 'value'
]
];
$exists = false;
$search = "orange";
array_walk_recursive($array, function ($val, $key) use (&$exists,$search) {
if ($search === $key) { $exists = true; }
});
echo ($exists?"Exists":"Doesn't exist");
Prints:
Exists
Example: http://sandbox.onlinephpfunctions.com/code/a3ffe7df25037476979f4b988c2f36f35742c217
Instead of using regex or strpos like the other answers, you could also simply split your $string on [ and resolve the keys one by one until there's only one key left. Then use that last key in combination with array_key_exists() to check for your item.
This should work for any amount of dimensions (eg fruit[apple][value][1]).
Example:
<?php
$arr = [
'fruits' => [
'orange' => 'value'
]
];
// Resolve keys by splitting on '[' and removing ']' from the results
$keys = 'fruits[orange]';
$keys = explode("[", $keys);
$keys = array_map(function($s) {
return str_replace("]", "", $s);
}, $keys);
// Resolve item.
// Stop before the last key.
$item = $arr;
for($i = 0; $i < count($keys) - 1; $i++) {
$item = $item[$keys[$i]];
}
// Check if the last remaining key exists.
if(array_key_exists($keys[count($keys)-1], $item)) {
// do things
}
You can explode and check the indices of the array.
$array = array(
'fruits' => [
'apple' => 'value',
'orange' => 'value'
],
'vegetables' => [
'onion' => 'value',
'carrot' => 'value'
]);
$string = 'fruits[orange]';
$indexes = (preg_split( "/(\[|\])/", $string));
$first_index= $indexes[0];
$seconnd_index= $indexes[1];
if(isset($array[$first_index][$seconnd_index]))
{
echo "exist";
}
else
{
echo "not exist";
}
DEMO