(PHP 4 >= 4.0.6, PHP 5, PHP 7)
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Example #1 array_map() ����
<?php
function cube($n)
{
return($n * $n * $n);
}
$a = array(1, 2, 3, 4, 5);
$b = array_map("cube", $a);
print_r($b);
?>
��ʹ�� $b ��Ϊ��
Array ( [0] => 1 [1] => 8 [2] => 27 [3] => 64 [4] => 125 )
Example #2 array_map() ʹ���������� (PHP 5.3.0 ��)
<?php
$func = function($value) {
return $value * 2;
};
print_r(array_map($func, range(1, 5)));
?>
Array ( [0] => 2 [1] => 4 [2] => 6 [3] => 8 [4] => 10 )
Example #3 array_map()��ʹ�ø��������
<?php
function show_Spanish($n, $m)
{
return("The number $n is called $m in Spanish");
}
function map_Spanish($n, $m)
{
return(array($n => $m));
}
$a = array(1, 2, 3, 4, 5);
$b = array("uno", "dos", "tres", "cuatro", "cinco");
$c = array_map("show_Spanish", $a, $b);
print_r($c);
$d = array_map("map_Spanish", $a , $b);
print_r($d);
?>
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// printout of $c Array ( [0] => The number 1 is called uno in Spanish [1] => The number 2 is called dos in Spanish [2] => The number 3 is called tres in Spanish [3] => The number 4 is called cuatro in Spanish [4] => The number 5 is called cinco in Spanish ) // printout of $d Array ( [0] => Array ( [1] => uno ) [1] => Array ( [2] => dos ) [2] => Array ( [3] => tres ) [3] => Array ( [4] => cuatro ) [4] => Array ( [5] => cinco ) )
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Example #4 ��ά���飺�������飬�ڲ���������
<?php
$a = array(1, 2, 3, 4, 5);
$b = array("one", "two", "three", "four", "five");
$c = array("uno", "dos", "tres", "cuatro", "cinco");
$d = array_map(null, $a, $b, $c);
print_r($d);
?>
�������̻������
Array ( [0] => Array ( [0] => 1 [1] => one [2] => uno ) [1] => Array ( [0] => 2 [1] => two [2] => dos ) [2] => Array ( [0] => 3 [1] => three [2] => tres ) [3] => Array ( [0] => 4 [1] => four [2] => cuatro ) [4] => Array ( [0] => 5 [1] => five [2] => cinco ) )
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Example #5 array_map() ����key���� string
<?php
$arr = array("stringkey" => "value");
function cb1($a) {
return array ($a);
}
function cb2($a, $b) {
return array ($a, $b);
}
var_dump(array_map("cb1", $arr));
var_dump(array_map("cb2", $arr, $arr));
var_dump(array_map(null, $arr));
var_dump(array_map(null, $arr, $arr));
?>
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array(1) { ["stringkey"]=> array(1) { [0]=> string(5) "value" } } array(1) { [0]=> array(2) { [0]=> string(5) "value" [1]=> string(5) "value" } } array(1) { ["stringkey"]=> string(5) "value" } array(1) { [0]=> array(2) { [0]=> string(5) "value" [1]=> string(5) "value" } }