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PHP array_walk_recursive() Function

Definition and Usage

The array_walk_recursive() function runs each array element in a user-made function. The array's keys and values are parameters in the function. The difference between this function and the array_walk() function is that with this function you can work with deeper arrays (an array inside an array). Returns True or False

Syntax

array_walk_recursive(array,function,parameter)

Parameter	Description
array	Required. Specifying an array
function	Required. The name of the user-made function
parameter	Optional. Specifies a parameter to the user-made function

Tips and Notes

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

Example

<?php
function myfunction($value,$key) 
{
echo "The key $key has the value $value<br />";
}
$a1=array("a"=>"Cat","b"=>"Dog");
$a2=array($a1,"1"=>"Bird","2"=>"Horse");
array_walk_recursive($a2,"myfunction");
?>

The output of the code above will be:

The key a has the value Cat
The key b has the value Dog
The key 1 has the value Bird
The key 2 has the value Horse

Complete PHP Array Reference