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PHP array_replace() Function

< PHP Array Reference

Example

Replace the values of the first array ($a1) with the values from the second array ($a2):

<?php
$a1=array("red","green");
$a2=array("blue","yellow");
print_r(array_replace($a1,$a2));
?>
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Definition and Usage

The array_replace() function replaces the values of the first array with the values from following arrays.

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

If a key from array1 exists in array2, values from array1 will be replaced by the values from array2. If the key only exists in array1, it will be left as it is (See Example 1 below).

If a key exist in array2 and not in array1, it will be created in array1 (See Example 2 below).

If multiple arrays are used, values from later arrays will overwrite the previous ones (See Example 3 below).

Tip: Use array_replace_recursive() to replace the values of array1 with the values from following arrays recursively.


Syntax

array_replace(array1,array2,array3...)

Parameter Description
array1 Required. Specifies an array
array2 Optional. Specifies an array which will replace the values of array1
array3,... Optional. Specifies more arrays to replace the values of array1 and array2, etc. Values from later arrays will overwrite the previous ones.

Technical Details

Return Value: Returns the replaced array, or NULL if an error occurs
PHP Version: 5.3.0+

More Examples

Example 1

If a key from array1 exists in array2, and if the key only exists in array1:

<?php
$a1=array("a"=>"red","b"=>"green");
$a2=array("a"=>"orange","burgundy");
print_r(array_replace($a1,$a2));
?>
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Example 2

If a key exists in array2 and not in array1:

<?php
$a1=array("a"=>"red","green");
$a2=array("a"=>"orange","b"=>"burgundy");
print_r(array_replace($a1,$a2));
?>
Run example »

Example 3

Using three arrays - the last array ($a3) will overwrite the previous ones ($a1 and $a2):

<?php
$a1=array("red","green");
$a2=array("blue","yellow");
$a3=array("orange","burgundy");
print_r(array_replace($a1,$a2,$a3));
?>
Run example »

Example 4

Using numeric keys - If a key exists in array2 and not in array1:

<?php
$a1=array("red","green","blue","yellow");
$a2=array(0=>"orange",3=>"burgundy");
print_r(array_replace($a1,$a2));
?>
Run example »

< PHP Array Reference