{"id":2103,"date":"2017-03-24T18:20:04","date_gmt":"2017-03-24T12:50:04","guid":{"rendered":"https:\/\/www.wikitechy.com\/technology\/?p=2103"},"modified":"2018-10-24T11:53:21","modified_gmt":"2018-10-24T06:23:21","slug":"difference-array_map-array_walk-array_filter","status":"publish","type":"post","link":"https:\/\/www.wikitechy.com\/technology\/difference-array_map-array_walk-array_filter\/","title":{"rendered":"Difference between array_map, array_walk and array_filter"},"content":{"rendered":"

array_map:<\/span><\/h2>\n

(PHP 4 >= 4.0.6, PHP 5, PHP 7)
\narray_map \u2014 Applies the callback to the elements of the given arrays<\/p>\n

Description:<\/span><\/h3>\n
Php Code<\/span> <\/div> 
array array_map ( callable $callback , array $array1 [, array $... ] )<\/code><\/pre> <\/div>\n[ad type=”banner”]\n
array_map() returns an array<\/a> containing all the elements of array1 after applying the callback function<\/a> to each one.<\/p>\n
The number of parameters that the callback function accepts should match the number of arrays passed to the array_map()<\/p>\n
Example #1<\/span><\/h3>\n
array_map() example:<\/span><\/strong><\/h4>\n
 
 Php Code<\/span> <\/div> 
<?phpfunction cube($n){    return($n * $n * $n);}$a = array(1, 2, 3, 4, 5);$b = array_map("cube", $a);print_r($b);?><\/code><\/pre> <\/div>\n
This makes $b have:<\/span><\/h4>\n
 
 Php Code<\/span> <\/div> 
Array(    [0] => 1    [1] => 8    [2] => 27    [3] => 64    [4] => 125)<\/code><\/pre> <\/div>\n
array_filter<\/span><\/h2>\n
(PHP 4 >= 4.0.6, PHP 5, PHP 7)
\narray_filter \u2014 Filters elements of an array using a callback function<\/p>\n
Description<\/span><\/h3>\n
 
 Php Code<\/span> <\/div> 
array array_filter ( array $array [, callable $callback [, int $flag = 0 ]] )<\/code><\/pre> <\/div>\n
Iterates over each value in the array passing them to the callback function.<\/p>\n
If the callback function returns true, the current value from array is returned into the result array. Array keys are preserved.<\/p>\n
Example #2<\/span><\/h3>\n
array_filter() without callback<\/strong><\/span><\/p>\n
 
 Php Code<\/span> <\/div> 
<?php$entry = array(             0 => 'foo',             1 => false,             2 => -1,             3 => null,             4 => ''          );print_r(array_filter($entry));?><\/code><\/pre> <\/div>\n[ad type=”banner”]\n
The above example will output:<\/span><\/h4>\n
 
 Php Code<\/span> <\/div> 
Array(    [0] => foo    [2] => -1)<\/code><\/pre> <\/div>\n
array_walk<\/span><\/h2>\n
(PHP 4, PHP 5, PHP 7)
\narray_walk \u2014 Apply a user supplied function to every member of an array<\/p>\n
Description :<\/span><\/h3>\n
 
 Php Code<\/span> <\/div> 
bool array_walk ( array &$array , callable $callback [, mixed $userdata = NULL ] )<\/code><\/pre> <\/div>\n