"red","b"=>"green","c"=>"blue"); $a2=array("a"=>"red","c"=>"blue","d"=>"pink"); $result=array_diff_key($a1,$a2); print_r($result); ?>"> "red","b"=>"green","c"=>"blue"); $a2=array("a"=>"red","c"=>"blue","d"=>"pink"); $result=array_diff_key($a1,$a2); print_r($result); ?>" />
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❮ Func Mysqli Insert Id Func Misc Eval ❯

PHP array_diff_key() Function

Complete PHP Array Reference Manual

Example

Compare the keys of two arrays and return the difference:

<?php
$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("a"=>"red","c"=>"blue","d"=>"pink");

$result=array_diff_key($a1,$a2);
print_r($result);
?>

Definition and Usage

The array_diff_key() function is used to compare the keys of two (or more) arrays and return the difference.

This function compares the keys of two (or more) arrays and returns an array containing all the keys from the first array that are not present in any of the other arrays.


Syntax

Parameter Description
array1 Required. The first array to compare with other arrays.
array2 Required. An array to compare against the first array.
array3,... Optional. Additional arrays to compare against the first array.

Technical Details

Return Value: Returns an array containing all the keys from the first array that are not present in any of the other arrays.
PHP Version: 5.1+
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More Examples

Example 1

Compare the keys of two numerical arrays and return the difference:

<?php
$a1=array("red","green","blue","yellow");
$a2=array("red","green","blue");

$result=array_diff_key($a1,$a2);
print_r($result);
?>

Example 2

Compare the keys of three arrays and return the difference:

<?php
$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("c"=>"yellow","d"=>"black","e"=>"brown");
$a3=array("f"=>"green","c"=>"purple","g"=>"red");

$result= array_diff_key($a1,$a2,$a3);
print_r($result);
?>

❮ Func Mysqli Insert Id Func Misc Eval ❯