Compare two arrays with built-in function to compare keys and a user function to compare values and return the differences in PHP

Description

The following code shows how to compare two arrays with built-in function to compare keys and a user function to compare values and return the differences.

Example

//from  w  ww.  j  a va 2s  .  c  o  m
<?php
function myfunction($a,$b){
   if ($a===$b){
     return 0;
   }
   return ($a>$b)?1:-1;
}

$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("a"=>"red","b"=>"blue","c"=>"green");

$result=array_udiff_assoc($a1,$a2,"myfunction");
print_r($result);
?>

The code above generates the following result.