PHP array_map() Function

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# PHP array_map() Function

Complete PHP Array Reference

## Definition and Usage

The array_map() function sends each value of an array to a user-made function, and returns an array with new values, given by the user-made function.

## Syntax

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

Parameter | Description
--- | ---
function | Required. The name of the user-made function, or null
array1 | Required. Specifies an array
array2 | Optional. Specifies an array
array3 | Optional. Specifies an array

## Tips and Notes

Tip: You can assign one array to the function, or as many as you like.

## Example 1

    <?php
    function myfunction($v)
    {
    if ($v==="Dog")
    	{
    	return "Fido";
    	}
    return $v;
    }
    $a=array("Horse","Dog","Cat");
    print_r(array_map("myfunction",$a));
    ?>

The output of the code above will be:

    Array ( [0] => Horse [1] => Fido [2] => Cat )

## Example 2

Using the more than one parameter.

    <?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));
    ?>

The output of the code above will be:

    Array ( [0] => different [1] => same [2] => different )

## Example 3

Look what happens if you assign null as the functionname:

    <?php
    $a1=array("Dog","Cat");
    $a2=array("Puppy","Kitten");
    print_r(array_map(null,$a1,$a2));
    ?>

The output of the code above will be:

    Array (
    [0] => Array ( [0] => Dog [1] => Puppy )
    [1] => Array ( [0] => Cat [1] => Kitten )
    )

Complete PHP Array Reference

From http://www.w3schools.com (Copyright Refsnes Data)