PHP array_map () function

Examples

The function is applied to each value in the array, each value is multiplied by itself, and returns an array with the new values:

<?php
function myfunction($v)
{
return($v*$v);
}

$a=array(1,2,3,4,5);
print_r(array_map("myfunction",$a));
?>

Running instance »

Definition and Usage

array_map () function to a user-defined function is applied to each value in the array, and returns the user-defined function role after an array with the new values.

Tip: You can enter a function to one or more arrays.

grammar

array_map( myfunction,array1,array2,array3 ...)

参数	描述
myfunction	必需。用户自定义函数的名称，或者是 null。
array1	必需。规定数组。
array2	可选。规定数组。
array3	可选。规定数组。

technical details

return value:	Returns an array array1 values of user-defined function after the action.
PHP version:	4.0.6+

More examples

Example 1

Using a user-defined function to change the value of the array:

<?php
function myfunction($v)
{
if ($v==="Dog")
{
return "Fido";
}
return $v;
}

$a=array("Horse","Dog","Cat");
print_r(array_map("myfunction",$a));
?>

Running instance »

Example 2

Use two arrays:

<?php
function myfunction($v1,$v2)
{
if ($v1===$v2)
{
return "same";
}
return "different";
}

$a1=array("Horse","Dog","Cat");
$a2=array("Cow","Dog","Rat");
print_r(array_map("myfunction",$a1,$a2));
?>

Running instance »

Example 3

All letters to uppercase values in the array:

<?php
function myfunction($v)
{
$v=strtoupper($v);
return $v;
}

$a=array("Animal" => "horse", "Type" => "mammal");
print_r(array_map("myfunction",$a));
?>

Running instance »