Related
I have an array with corresponding value.
Array
(
[0] => BBsma=200
[1] => SMAperiod=300
[2] => SMA1=400
[3] => SMA2=500
[4] => EMAperiod=300
[5] => EMA1=24
[6] => EMA2=8
)
Now I want to match a certain string like for example BBsma that should return 200. Any help?
Got the array using these codes.
$txt = file_get_contents('INDICATORS.txt');
$rows = explode("\n", $txt);
array_shift($rows);
INDICATORS.txt content
BBperiod=100
BBsma=200
SMAperiod=300
SMA1=400
SMA2=500
EMAperiod=300
EMA1=24
EMA2=8
After you explode your text to the lines use this code:
for($i=0;$i<sizeof($rows);$i++)
{
$temp=explode("=",$rows[$i]);
if(sizeof($temp)==2)
{
$arr[$temp[0]]=$temp[1];
}
}
You will have named array in $arr
if you want to cast second part to int, you just change 6-line to this:
$arr[$temp[0]]=intval($temp[1]);
You could iterate over every line of your array and find the value with a regular match.
Code:
$txt = file_get_contents('INDICATORS.txt');
$rows = explode("\n", $txt);
/*
$rows = [
"BBsma=200",
"SMAperiod=300",
"SMA1=400",
"SMA2=500",
"EMAperiod=300",
"EMA1=24",
"EMA2=8",
];
*/
foreach ($rows as $k=>$v) {
if (preg_match("/(BBsma|SMAperiod|EMAperiod)=([0-9]+)/", $v, $matches)) {
echo "found value " . $matches[2] . " for entry " . $matches[1] . " in line " . $k . PHP_EOL;
}
}
Output:
found value 200 for entry BBsma in line 0
found value 300 for entry SMAperiod in line 1
found value 300 for entry EMAperiod in line 4
You can explode by new line as PHP_EOL like this
$col = "BBsma";
$val = "";
foreach(explode(PHP_EOL,$str) as $row){
$cols = explode("=",$row);
if(trim($cols[0]) == $col){
$val = $cols[1];
break;
}
}
echo "Value $col is : $val";
Live Demo
If your going to use the array a few times, it may be easier to read the file into an associative array in the first place...
$rows = [];
$file = "INDICATORS.txt";
$data = file($file, FILE_IGNORE_NEW_LINES);
foreach ( $data as $item ) {
$row = explode("=", $item);
$rows [$row[0]] = $row[1];
}
echo "EMA1 =".$rows['EMA1'];
This doesn't do the array_shift() but not sure why it's used, but easy to add back in.
This outputs...
EMA1 =24
I think that using array filter answers your question the best. It returns an array of strings with status code 200. If you wanted to have better control later on and sort / search through codes. I would recommend using array_walk to create some sort of multi dimensional array. Either solution will work.
<?php
$arr = [
"BBsma=200",
"SMAperiod=300",
"SMA1=400",
"SMA2=500",
"EMAperiod=300",
"EMA1=24",
"EMA2=8",
];
$filtered = array_filter($arr,"filter");
function filter($element) {
return strpos($element,"=200");
}
var_dump($filtered); // Returns array with all matching =200 codes: BBSMA=200
Output:
array (size=1)
0 => string 'BBsma=200' (length=9)
Should you want to do more I would recommend doing something like this:
///////// WALK The array for better control / manipulation
$walked = [];
array_walk($arr, function($item, $key) use (&$walked) {
list($key,$value) = explode("=", $item);
$walked[$key] = $value;
});
var_dump($walked);
This is going to give you an array with the parameter as the key and status code as it's value. I originally posted array_map but quickly realized array walk was a cleaner solution.
array (size=7)
'BBsma' => string '200' (length=3)
'SMAperiod' => string '300' (length=3)
'SMA1' => string '400' (length=3)
'SMA2' => string '500' (length=3)
'EMAperiod' => string '300' (length=3)
'EMA1' => string '24' (length=2)
'EMA2' => string '8' (length=1)
Working with the array becomes a lot easier this way:
echo $walked['BBsma']; // 200
$anything = array("BBsma"=>"200", "SMAperiod"=>"300", "SMA1"=>"400");
echo "the value is " . $anything['BBsma'];
This will return 200
This is the initial string:-
NAME=Marco\nLOCATION=localhost\nSECRET=fjsdgfsjfdskffuv=\n
This is my solution although the "=" in the end of the string does not appear in the array
$env = file_get_contents(base_path() . '/.env');
// Split string on every " " and write into array
$env = preg_split('/\s+/', $env);
//create new array to push data in the foreach
$newArray = array();
foreach($env as $val){
// Split string on every "=" and write into array
$result = preg_split ('/=/', $val);
if($result[0] && $result[1])
{
$newArray[$result[0]] = $result[1];
}
}
print_r($newArray);
This is the result I get:
Array ( [Name] => Marco [LOCATION] => localhost [SECRET] => fjsdgfsjfdskffuv )
But I need :
Array ( [Name] => Marco [LOCATION] => localhost [SECRET] => fjsdgfsjfdskffuv= )
You can use the limit parameter of preg_split to make it only split the string once
http://php.net/manual/en/function.preg-split.php
you should change
$result = preg_split ('/=/', $val);
to
$result = preg_split ('/=/', $val, 2);
Hope this helps
$string = 'NAME=Marco\nLOCATION=localhost\nSECRET=fjsdgfsjfdskffuv=\n';
$strXlate = [ 'NAME=' => '"NAME":"' ,
'LOCATION=' => '","LOCATION":"',
'SECRET=' => '","SECRET":"' ,
'\n' => '' ];
$jsonified = '{'.strtr($string, $strXlate).'"}';
$array = json_decode($jsonified, true);
This is based on 1) translation using strtr(), preparing an array in json format and then using a json_decode which blows it up nicely into an array...
Same result, other approach...
You can also use parse_str to parse URL syntax-like strings to name-value pairs.
Based on your example:
$newArray = [];
$str = file_get_contents(base_path() . '/.env');
$env = explode("\n", $str);
array_walk(
$env,
function ($i) use (&$newArray) {
if (!$i) { return; }
$tmp = [];
parse_str($i, $tmp);
$newArray[] = $tmp;
}
);
var_dump($newArray);
Of course, you need to put some sanity check in the function since it can insert some strange stuff in the array like values with empty string keys, and whatnot.
I have this cases with strings in PHP:
*nJohn*sSmith*fGeorge#*nHenry*sFord
and wish to create an array with
[name],[surname],[fathers] as indexes so it will produce
name_array[1] = (
[name] => 'John',
[surname] => 'Smith',
[fathers] => 'George'
)
name_array[2]=(
[name] => 'Henry',
[surname] => 'Ford'
)
and so on.
How to do it using preg_split in PHP??
Thanks!
I'd use preg_match_all to get the names. If your string is consistent I think you could do:
$string = '*nJohn*sSmith*fGeorge#*nHenry*sFord';
preg_match_all('/\*n(?<givenname>.*?)\*s(?<surname>.*?)(?:\*f(?<middlename>.*?))?(?:#|$)/', $string, $matches);
print_r($matches);
Regex demo: https://regex101.com/r/1hKzvM/1/
PHP demo: https://eval.in/784879
Solution without using regex:
$string = '*nJohn*sSmith*fGeorge#*nHenry*sFord';
$result = array();
$persons = explode('#', $string);
foreach ($persons as $person) {
$identials = explode('*', $person);
unset($r);
foreach ($identials as $idential) {
if(!$idential){
continue; //empty string
}
switch ($idential[0]) { //first character
case 'n':
$key = 'name';
break;
case 's':
$key = 'surename';
break;
case 'f':
$key = 'fathers';
break;
}
$r[$key] = substr($idential, 1);
}
$result[] = $r;
}
This function will produce the result that you want ! but consider it's not the only way and not the 100% correct way ! i used preg_split as u asked
function splitMyString($str){
$array_names = [];
$mainString = explode('#', $str);
$arr1 = preg_split("/\*[a-z]/", $mainString[0]);
unset($arr1[0]);
$arr1_values = array_values($arr1);
$arr1_keys = ['name','surname','fathers'];
$result1 = array_combine($arr1_keys, $arr1_values);
// second part of string
$arr2 = preg_split("/\*[a-z]/", $mainString[1]);
unset($arr2[0]);
$arr2_values = array_values($arr2);
$arr2_keys = ['name','surname'];
$arr2 = array_combine($arr2_keys, $arr2_values);
$array_names[] = $arr1;
$array_names[] = $arr2;
return $array_names;
}
// test result !
print_r(splitMyString("*nJohn*sSmith*fGeorge#*nHenry*sFord"));
thanks to all!
For some reason the site blocks my voting for some 'reputation' reason which I find not-fully democracy compliant! On the other hand who cares about democracy these days!
Nevertheless I am using solution #2, without indicating that solution 1 or 3 are not great!
Regards.
However inspired by your answers I came up with mine also, here it is!
$string = '*nJohn*sSmith*fGeorge#*nHenry*sFord';
split_to_key ( $string, array('n'=>'Name','s'=>'Surname','f'=>'Middle'));
function split_to_key ( $string,$ind=array() )
{
$far=null;
$i=0;
$fbig=preg_split('/#/',$string,-1,PREG_SPLIT_NO_EMPTY);
foreach ( $fbig as $fsmall ) {
$f=preg_split('/\*/u',$fsmall,-1,PREG_SPLIT_NO_EMPTY);
foreach ( $f as $fs ) {
foreach( array_keys($ind) as $key ) {
if( preg_match ('/^'.$key.'/u',$fs ) ) {
$fs=preg_replace('/^'.$key.'/u','',$fs);
$far[$i][$ind[$key]]=$fs;
}
}
}
$i++;
}
print_r($far);
}
Like Chris, I wouldn't use preg_split(). My method uses just one preg() function and one loop to completely prepare the filtered output in your desired format (notice my output is 0-indexed, though).
Input (I extended your input sample for testing):
$string='*nJohn*sSmith*fGeorge#*nHenry*sFord#*nJames*sWashington#*nMary*sMiller*fRichard';
Method (PHP Demo & Regex Demo):
if(preg_match_all('/\*n([^*]*)\*s([^*]*)(?:\*f([^#]*))?(?=#|$)/', $string, $out)){
$out=array_slice($out,1); // /prepare for array_column()
foreach($out[0] as $i=>$v){
$name_array[$i]=array_combine(['name','surname','father'],array_column($out,$i));
if($name_array[$i]['father']==''){unset($name_array[$i]['father']);}
}
}
var_export($name_array);
Output:
array (
0 =>
array (
'name' => 'John',
'surname' => 'Smith',
'father' => 'George',
),
1 =>
array (
'name' => 'Henry',
'surname' => 'Ford',
),
2 =>
array (
'name' => 'James',
'surname' => 'Washington',
),
3 =>
array (
'name' => 'Mary',
'surname' => 'Miller',
'father' => 'Richard',
),
)
My regex pattern is optimized for speed by using "negative character classes". I elected to not use the named capture groups because they nearly double the output array size from preg_match_all() and that array requires further preparation anyhow.
Take a look at this code:
$GET = array();
$key = 'one=1';
$rule = explode('=', $key);
/* array_push($GET, $rule[0] => $rule[1]); */
I'm looking for something like this so that:
print_r($GET);
/* output: $GET[one => 1, two => 2, ...] */
Is there a function to do this? (because array_push won't work this way)
Nope, there is no array_push() equivalent for associative arrays because there is no way determine the next key.
You'll have to use
$arrayname[indexname] = $value;
Pushing a value into an array automatically creates a numeric key for it.
When adding a key-value pair to an array, you already have the key, you don't need one to be created for you. Pushing a key into an array doesn't make sense. You can only set the value of the specific key in the array.
// no key
array_push($array, $value);
// same as:
$array[] = $value;
// key already known
$array[$key] = $value;
You can use the union operator (+) to combine arrays and keep the keys of the added array. For example:
<?php
$arr1 = array('foo' => 'bar');
$arr2 = array('baz' => 'bof');
$arr3 = $arr1 + $arr2;
print_r($arr3);
// prints:
// array(
// 'foo' => 'bar',
// 'baz' => 'bof',
// );
So you could do $_GET += array('one' => 1);.
There's more info on the usage of the union operator vs array_merge in the documentation at http://php.net/manual/en/function.array-merge.php.
I wonder why the simplest method hasn't been posted yet:
$arr = ['company' => 'Apple', 'product' => 'iPhone'];
$arr += ['version' => 8];
I would like to add my answer to the table and here it is :
//connect to db ...etc
$result_product = /*your mysql query here*/
$array_product = array();
$i = 0;
foreach ($result_product as $row_product)
{
$array_product [$i]["id"]= $row_product->id;
$array_product [$i]["name"]= $row_product->name;
$i++;
}
//you can encode the array to json if you want to send it to an ajax call
$json_product = json_encode($array_product);
echo($json_product);
hope that this will help somebody
Exactly what Pekka said...
Alternatively, you can probably use array_merge like this if you wanted:
array_merge($_GET, array($rule[0] => $rule[1]));
But I'd prefer Pekka's method probably as it is much simpler.
I was just looking for the same thing and I realized that, once again, my thinking is different because I am old school. I go all the way back to BASIC and PERL and sometimes I forget how easy things really are in PHP.
I just made this function to take all settings from the database where their are 3 columns. setkey, item (key) & value (value) and place them into an array called settings using the same key/value without using push just like above.
Pretty easy & simple really
// Get All Settings
$settings=getGlobalSettings();
// Apply User Theme Choice
$theme_choice = $settings['theme'];
.. etc etc etc ....
function getGlobalSettings(){
$dbc = mysqli_connect(wds_db_host, wds_db_user, wds_db_pass) or die("MySQL Error: " . mysqli_error());
mysqli_select_db($dbc, wds_db_name) or die("MySQL Error: " . mysqli_error());
$MySQL = "SELECT * FROM systemSettings";
$result = mysqli_query($dbc, $MySQL);
while($row = mysqli_fetch_array($result))
{
$settings[$row['item']] = $row['value']; // NO NEED FOR PUSH
}
mysqli_close($dbc);
return $settings;
}
So like the other posts explain... In php there is no need to "PUSH" an array when you are using
Key => Value
AND... There is no need to define the array first either.
$array=array();
Don't need to define or push. Just assign $array[$key] = $value; It is automatically a push and a declaration at the same time.
I must add that for security reasons, (P)oor (H)elpless (P)rotection, I means Programming for Dummies, I mean PHP.... hehehe I suggest that you only use this concept for what I intended. Any other method could be a security risk. There, made my disclaimer!
This is the solution that may useful for u
Class Form {
# Declare the input as property
private $Input = [];
# Then push the array to it
public function addTextField($class,$id){
$this->Input ['type'][] = 'text';
$this->Input ['class'][] = $class;
$this->Input ['id'][] = $id;
}
}
$form = new Form();
$form->addTextField('myclass1','myid1');
$form->addTextField('myclass2','myid2');
$form->addTextField('myclass3','myid3');
When you dump it. The result like this
array (size=3)
'type' =>
array (size=3)
0 => string 'text' (length=4)
1 => string 'text' (length=4)
2 => string 'text' (length=4)
'class' =>
array (size=3)
0 => string 'myclass1' (length=8)
1 => string 'myclass2' (length=8)
2 => string 'myclass3' (length=8)
'id' =>
array (size=3)
0 => string 'myid1' (length=5)
1 => string 'myid2' (length=5)
2 => string 'myid3' (length=5)
A bit late but if you don't mind a nested array you could take this approach:
$main_array = array(); //Your array that you want to push the value into
$value = 10; //The value you want to push into $main_array
array_push($main_array, array('Key' => $value));
To clarify,
if you output json_encode($main_array) that will look like [{"Key":"10"}]
A bit weird, but this worked for me
$array1 = array("Post Slider", "Post Slider Wide", "Post Slider");
$array2 = array("Tools Sliders", "Tools Sliders", "modules-test");
$array3 = array();
$count = count($array1);
for($x = 0; $x < $count; $x++){
$array3[$array1[$x].$x] = $array2[$x];
}
foreach($array3 as $key => $value){
$output_key = substr($key, 0, -1);
$output_value = $value;
echo $output_key.": ".$output_value."<br>";
}
$arr = array("key1"=>"value1", "key2"=>"value");
print_r($arr);
// prints array['key1'=>"value1", 'key2'=>"value2"]
The simple way:
$GET = array();
$key = 'one=1';
parse_str($key, $GET);
http://php.net/manual/de/function.parse-str.php
Example array_merge()....
$array1 = array("color" => "red", 2, 4);
$array2 = array("a", "b", "color" => "green", "shape" => "trapezoid", 4);
$result = array_merge($array1, $array2);
print_r($result);
Array([color] => green,[0] => 2,[1] => 4,[2] => a,[3] => b,[shape] => trapezoid,[4] => 4,)
I wrote a simple function:
function push(&$arr,$new) {
$arr = array_merge($arr,$new);
}
so that I can "upsert" new element easily:
push($my_array, ['a'=>1,'b'=>2])
2023
A lot of answers. Some helpful, others good but awkward. Since you don't need complicated and expensive arithmetic operations, loops etc. for a simple operation like adding an element to an array, here is my collection of One-Liner-Add-To-Array-Functions.
$array = ['a' => 123, 'b' => 456]; // init Array
$array['c'] = 789; // 1.
$array += ['d' => '012']; // 2.
$array = array_merge($array, ['e' => 345]); // 3.
$array = [...$array, 'f' => 678]; // 4.
print_r($array);
// Output:
/*
Array
(
[a] => 123
[b] => 456
[c] => 789
[d] => 012
[e] => 345
[f] => 678
)
*/
In 99,99% i use version 1. ($array['c'] = 789;). But i like version 4. That is the version with the splat operator (https://www.php.net/manual/en/migration56.new-features.php).
array_push($arr, ['key1' => $value1, 'key2' => value2]);
This works just fine.
creates the the key with its value in the array
hi i had same problem i find this solution you should use two arrays then combine them both
<?php
$fname=array("Peter","Ben","Joe");
$age=array("35","37","43");
$c=array_combine($fname,$age);
print_r($c);
?>
reference : w3schools
For add to first position with key and value
$newAarray = [newIndexname => newIndexValue] ;
$yourArray = $newAarray + $yourArray ;
There are some great example already given here. Just adding a simple example to push associative array elements to root numeric index index.
$intial_content = array();
if (true) {
$intial_content[] = array('name' => 'xyz', 'content' => 'other content');
}
array_push($GET, $GET['one']=1);
It works for me.
I usually do this:
$array_name = array(
'key1' => 'value1',
'key2' => 'value2',
'key3' => 'value3'
);
I have an associative array in the form key => value where key is a numerical value, however it is not a sequential numerical value. The key is actually an ID number and the value is a count. This is fine for most instances, however I want a function that gets the human-readable name of the array and uses that for the key, without changing the value.
I didn't see a function that does this, but I'm assuming I need to provide the old key and new key (both of which I have) and transform the array. Is there an efficient way of doing this?
$arr[$newkey] = $arr[$oldkey];
unset($arr[$oldkey]);
The way you would do this and preserve the ordering of the array is by putting the array keys into a separate array, find and replace the key in that array and then combine it back with the values.
Here is a function that does just that:
function change_key( $array, $old_key, $new_key ) {
if( ! array_key_exists( $old_key, $array ) )
return $array;
$keys = array_keys( $array );
$keys[ array_search( $old_key, $keys ) ] = $new_key;
return array_combine( $keys, $array );
}
if your array is built from a database query, you can change the key directly from the mysql statement:
instead of
"select ´id´ from ´tablename´..."
use something like:
"select ´id´ **as NEWNAME** from ´tablename´..."
The answer from KernelM is nice, but in order to avoid the issue raised by Greg in the comment (conflicting keys), using a new array would be safer
$newarr[$newkey] = $oldarr[$oldkey];
$oldarr=$newarr;
unset($newarr);
$array = [
'old1' => 1
'old2' => 2
];
$renameMap = [
'old1' => 'new1',
'old2' => 'new2'
];
$array = array_combine(array_map(function($el) use ($renameMap) {
return $renameMap[$el];
}, array_keys($array)), array_values($array));
/*
$array = [
'new1' => 1
'new2' => 2
];
*/
You could use a second associative array that maps human readable names to the id's. That would also provide a Many to 1 relationship. Then do something like this:
echo 'Widgets: ' . $data[$humanreadbleMapping['Widgets']];
If you want also the position of the new array key to be the same as the old one you can do this:
function change_array_key( $array, $old_key, $new_key) {
if(!is_array($array)){ print 'You must enter a array as a haystack!'; exit; }
if(!array_key_exists($old_key, $array)){
return $array;
}
$key_pos = array_search($old_key, array_keys($array));
$arr_before = array_slice($array, 0, $key_pos);
$arr_after = array_slice($array, $key_pos + 1);
$arr_renamed = array($new_key => $array[$old_key]);
return $arr_before + $arr_renamed + $arr_after;
}
Simple benchmark comparison of both solution.
Solution 1 Copy and remove (order lost, but way faster) https://stackoverflow.com/a/240676/1617857
<?php
$array = ['test' => 'value', ['etc...']];
$array['test2'] = $array['test'];
unset($array['test']);
Solution 2 Rename the key https://stackoverflow.com/a/21299719/1617857
<?php
$array = ['test' => 'value', ['etc...']];
$keys = array_keys( $array );
$keys[array_search('test', $keys, true)] = 'test2';
array_combine( $keys, $array );
Benchmark:
<?php
$array = ['test' => 'value', ['etc...']];
for ($i =0; $i < 100000000; $i++){
// Solution 1
}
for ($i =0; $i < 100000000; $i++){
// Solution 2
}
Results:
php solution1.php 6.33s user 0.02s system 99% cpu 6.356 total
php solution1.php 6.37s user 0.01s system 99% cpu 6.390 total
php solution2.php 12.14s user 0.01s system 99% cpu 12.164 total
php solution2.php 12.57s user 0.03s system 99% cpu 12.612 total
If your array is recursive you can use this function:
test this data:
$datos = array
(
'0' => array
(
'no' => 1,
'id_maquina' => 1,
'id_transaccion' => 1276316093,
'ultimo_cambio' => 'asdfsaf',
'fecha_ultimo_mantenimiento' => 1275804000,
'mecanico_ultimo_mantenimiento' =>'asdfas',
'fecha_ultima_reparacion' => 1275804000,
'mecanico_ultima_reparacion' => 'sadfasf',
'fecha_siguiente_mantenimiento' => 1275804000,
'fecha_ultima_falla' => 0,
'total_fallas' => 0,
),
'1' => array
(
'no' => 2,
'id_maquina' => 2,
'id_transaccion' => 1276494575,
'ultimo_cambio' => 'xx',
'fecha_ultimo_mantenimiento' => 1275372000,
'mecanico_ultimo_mantenimiento' => 'xx',
'fecha_ultima_reparacion' => 1275458400,
'mecanico_ultima_reparacion' => 'xx',
'fecha_siguiente_mantenimiento' => 1275372000,
'fecha_ultima_falla' => 0,
'total_fallas' => 0,
)
);
here is the function:
function changekeyname($array, $newkey, $oldkey)
{
foreach ($array as $key => $value)
{
if (is_array($value))
$array[$key] = changekeyname($value,$newkey,$oldkey);
else
{
$array[$newkey] = $array[$oldkey];
}
}
unset($array[$oldkey]);
return $array;
}
I like KernelM's solution, but I needed something that would handle potential key conflicts (where a new key may match an existing key). Here is what I came up with:
function swapKeys( &$arr, $origKey, $newKey, &$pendingKeys ) {
if( !isset( $arr[$newKey] ) ) {
$arr[$newKey] = $arr[$origKey];
unset( $arr[$origKey] );
if( isset( $pendingKeys[$origKey] ) ) {
// recursion to handle conflicting keys with conflicting keys
swapKeys( $arr, $pendingKeys[$origKey], $origKey, $pendingKeys );
unset( $pendingKeys[$origKey] );
}
} elseif( $newKey != $origKey ) {
$pendingKeys[$newKey] = $origKey;
}
}
You can then cycle through an array like this:
$myArray = array( '1970-01-01 00:00:01', '1970-01-01 00:01:00' );
$pendingKeys = array();
foreach( $myArray as $key => $myArrayValue ) {
// NOTE: strtotime( '1970-01-01 00:00:01' ) = 1 (a conflicting key)
$timestamp = strtotime( $myArrayValue );
swapKeys( $myArray, $key, $timestamp, $pendingKeys );
}
// RESULT: $myArray == array( 1=>'1970-01-01 00:00:01', 60=>'1970-01-01 00:01:00' )
Here is a helper function to achieve that:
/**
* Helper function to rename array keys.
*/
function _rename_arr_key($oldkey, $newkey, array &$arr) {
if (array_key_exists($oldkey, $arr)) {
$arr[$newkey] = $arr[$oldkey];
unset($arr[$oldkey]);
return TRUE;
} else {
return FALSE;
}
}
pretty based on #KernelM answer.
Usage:
_rename_arr_key('oldkey', 'newkey', $my_array);
It will return true on successful rename, otherwise false.
this code will help to change the oldkey to new one
$i = 0;
$keys_array=array("0"=>"one","1"=>"two");
$keys = array_keys($keys_array);
for($i=0;$i<count($keys);$i++) {
$keys_array[$keys_array[$i]]=$keys_array[$i];
unset($keys_array[$i]);
}
print_r($keys_array);
display like
$keys_array=array("one"=>"one","two"=>"two");
Easy stuff:
this function will accept the target $hash and $replacements is also a hash containing newkey=>oldkey associations.
This function will preserve original order, but could be problematic for very large (like above 10k records) arrays regarding performance & memory.
function keyRename(array $hash, array $replacements) {
$new=array();
foreach($hash as $k=>$v)
{
if($ok=array_search($k,$replacements))
$k=$ok;
$new[$k]=$v;
}
return $new;
}
this alternative function would do the same, with far better performance & memory usage, at the cost of losing original order (which should not be a problem since it is hashtable!)
function keyRename(array $hash, array $replacements) {
foreach($hash as $k=>$v)
if($ok=array_search($k,$replacements))
{
$hash[$ok]=$v;
unset($hash[$k]);
}
return $hash;
}
This page has been peppered with a wide interpretation of what is required because there is no minimal, verifiable example in the question body. Some answers are merely trying to solve the "title" without bothering to understand the question requirements.
The key is actually an ID number and the value is a count. This is
fine for most instances, however I want a function that gets the
human-readable name of the array and uses that for the key, without
changing the value.
PHP keys cannot be changed but they can be replaced -- this is why so many answers are advising the use of array_search() (a relatively poor performer) and unset().
Ultimately, you want to create a new array with names as keys relating to the original count. This is most efficiently done via a lookup array because searching for keys will always outperform searching for values.
Code: (Demo)
$idCounts = [
3 => 15,
7 => 12,
8 => 10,
9 => 4
];
$idNames = [
1 => 'Steve',
2 => 'Georgia',
3 => 'Elon',
4 => 'Fiona',
5 => 'Tim',
6 => 'Petra',
7 => 'Quentin',
8 => 'Raymond',
9 => 'Barb'
];
$result = [];
foreach ($idCounts as $id => $count) {
if (isset($idNames[$id])) {
$result[$idNames[$id]] = $count;
}
}
var_export($result);
Output:
array (
'Elon' => 15,
'Quentin' => 12,
'Raymond' => 10,
'Barb' => 4,
)
This technique maintains the original array order (in case the sorting matters), doesn't do any unnecessary iterating, and will be very swift because of isset().
If you want to replace several keys at once (preserving order):
/**
* Rename keys of an array
* #param array $array (asoc)
* #param array $replacement_keys (indexed)
* #return array
*/
function rename_keys($array, $replacement_keys) {
return array_combine($replacement_keys, array_values($array));
}
Usage:
$myarr = array("a" => 22, "b" => 144, "c" => 43);
$newkeys = array("x","y","z");
print_r(rename_keys($myarr, $newkeys));
//must return: array("x" => 22, "y" => 144, "z" => 43);
You can use this function based on array_walk:
function mapToIDs($array, $id_field_name = 'id')
{
$result = [];
array_walk($array,
function(&$value, $key) use (&$result, $id_field_name)
{
$result[$value[$id_field_name]] = $value;
}
);
return $result;
}
$arr = [0 => ['id' => 'one', 'fruit' => 'apple'], 1 => ['id' => 'two', 'fruit' => 'banana']];
print_r($arr);
print_r(mapToIDs($arr));
It gives:
Array(
[0] => Array(
[id] => one
[fruit] => apple
)
[1] => Array(
[id] => two
[fruit] => banana
)
)
Array(
[one] => Array(
[id] => one
[fruit] => apple
)
[two] => Array(
[id] => two
[fruit] => banana
)
)
This basic function handles swapping array keys and keeping the array in the original order...
public function keySwap(array $resource, array $keys)
{
$newResource = [];
foreach($resource as $k => $r){
if(array_key_exists($k,$keys)){
$newResource[$keys[$k]] = $r;
}else{
$newResource[$k] = $r;
}
}
return $newResource;
}
You could then loop through and swap all 'a' keys with 'z' for example...
$inputs = [
0 => ['a'=>'1','b'=>'2'],
1 => ['a'=>'3','b'=>'4']
]
$keySwap = ['a'=>'z'];
foreach($inputs as $k=>$i){
$inputs[$k] = $this->keySwap($i,$keySwap);
}
This function will rename an array key, keeping its position, by combining with index searching.
function renameArrKey($arr, $oldKey, $newKey){
if(!isset($arr[$oldKey])) return $arr; // Failsafe
$keys = array_keys($arr);
$keys[array_search($oldKey, $keys)] = $newKey;
$newArr = array_combine($keys, $arr);
return $newArr;
}
Usage:
$arr = renameArrKey($arr, 'old_key', 'new_key');
this works for renaming the first key:
$a = ['catine' => 'cat', 'canine' => 'dog'];
$tmpa['feline'] = $a['catine'];
unset($a['catine']);
$a = $tmpa + $a;
then, print_r($a) renders a repaired in-order array:
Array
(
[feline] => cat
[canine] => dog
)
this works for renaming an arbitrary key:
$a = ['canine' => 'dog', 'catine' => 'cat', 'porcine' => 'pig']
$af = array_flip($a)
$af['cat'] = 'feline';
$a = array_flip($af)
print_r($a)
Array
(
[canine] => dog
[feline] => cat
[porcine] => pig
)
a generalized function:
function renameKey($oldkey, $newkey, $array) {
$val = $array[$oldkey];
$tmp_A = array_flip($array);
$tmp_A[$val] = $newkey;
return array_flip($tmp_A);
}
There is an alternative way to change the key of an array element when working with a full array - without changing the order of the array.
It's simply to copy the array into a new array.
For instance, I was working with a mixed, multi-dimensional array that contained indexed and associative keys - and I wanted to replace the integer keys with their values, without breaking the order.
I did so by switching key/value for all numeric array entries - here: ['0'=>'foo']. Note that the order is intact.
<?php
$arr = [
'foo',
'bar'=>'alfa',
'baz'=>['a'=>'hello', 'b'=>'world'],
];
foreach($arr as $k=>$v) {
$kk = is_numeric($k) ? $v : $k;
$vv = is_numeric($k) ? null : $v;
$arr2[$kk] = $vv;
}
print_r($arr2);
Output:
Array (
[foo] =>
[bar] => alfa
[baz] => Array (
[a] => hello
[b] => world
)
)
best way is using reference, and not using unset (which make another step to clean memory)
$tab = ['two' => [] ];
solution:
$tab['newname'] = & $tab['two'];
you have one original and one reference with new name.
or if you don't want have two names in one value is good make another tab and foreach on reference
foreach($tab as $key=> & $value) {
if($key=='two') {
$newtab["newname"] = & $tab[$key];
} else {
$newtab[$key] = & $tab[$key];
}
}
Iterration is better on keys than clone all array, and cleaning old array if you have long data like 100 rows +++ etc..
One which preservers ordering that's simple to understand:
function rename_array_key(array $array, $old_key, $new_key) {
if (!array_key_exists($old_key, $array)) {
return $array;
}
$new_array = [];
foreach ($array as $key => $value) {
$new_key = $old_key === $key
? $new_key
: $key;
$new_array[$new_key] = $value;
}
return $new_array;
}
Here is an experiment (test)
Initial array (keys like 0,1,2)
$some_array[] = '6110';//
$some_array[] = '6111';//
$some_array[] = '6210';//
I must change key names to for example human_readable15, human_readable16, human_readable17
Something similar as already posted. During each loop i set necessary key name and remove corresponding key from the initial array.
For example, i inserted into mysql $some_array got lastInsertId and i need to send key-value pair back to jquery.
$first_id_of_inserted = 7;//lastInsertId
$last_loop_for_some_array = count($some_array);
for ($current_loop = 0; $current_loop < $last_loop_for_some_array ; $current_loop++) {
$some_array['human_readable'.($first_id_of_inserted + $current_loop)] = $some_array[$current_loop];//add new key for intial array
unset( $some_array[$current_loop] );//remove already renamed key from array
}
And here is the new array with renamed keys
echo '<pre>', print_r($some_array, true), '</pre>$some_array in '. basename(__FILE__, '.php'). '.php <br/>';
If instead of human_readable15, human_readable16, human_readable17 need something other. Then could create something like this
$arr_with_key_names[] = 'human_readable';
$arr_with_key_names[] = 'something_another';
$arr_with_key_names[] = 'and_something_else';
for ($current_loop = 0; $current_loop < $last_loop_for_some_array ; $current_loop++) {
$some_array[$arr_with_key_names[$current_loop]] = $some_array[$current_loop];//add new key for intial array
unset( $some_array[$current_loop] );//remove already renamed key from array
}
Hmm, I'm not test before, but I think this code working
function replace_array_key($data) {
$mapping = [
'old_key_1' => 'new_key_1',
'old_key_2' => 'new_key_2',
];
$data = json_encode($data);
foreach ($mapping as $needed => $replace) {
$data = str_replace('"'.$needed.'":', '"'.$replace.'":', $data);
}
return json_decode($data, true);
}
You can write simple function that applies the callback to the keys of the given array. Similar to array_map
<?php
function array_map_keys(callable $callback, array $array) {
return array_merge([], ...array_map(
function ($key, $value) use ($callback) { return [$callback($key) => $value]; },
array_keys($array),
$array
));
}
$array = ['a' => 1, 'b' => 'test', 'c' => ['x' => 1, 'y' => 2]];
$newArray = array_map_keys(function($key) { return 'new' . ucfirst($key); }, $array);
echo json_encode($array); // {"a":1,"b":"test","c":{"x":1,"y":2}}
echo json_encode($newArray); // {"newA":1,"newB":"test","newC":{"x":1,"y":2}}
Here is a gist https://gist.github.com/vardius/650367e15abfb58bcd72ca47eff096ca#file-array_map_keys-php.