Example: array_diff() vs. array_diff_assoc()

array_diff_example.php

<?php
$a = array('z'=>1, 'a'=>5, 'e'=>'7');
$b = array('a'=>3, 'g'=>5, 'x'=>7);
$c = array_diff($a, $b);
$d = array_diff_assoc($a, $b);
echo '<b>$a</b> = ';
var_dump($a);
echo '</br><b>$b</b> = ';
var_dump($b);
echo '</br><h2>array_diff($a, $b) Result</h2>';
var_dump($c);
echo '</br><h2>array_diff_assoc($a, $b) Result</h2>';
var_dump($d);

Add in array_diff_key as well.

<?php
$a = array('z'=>1, 'a'=>5, 'e'=>'7');
$b = array('a'=>5, 'g'=>3, 'z'=>7);
$c = array_diff($a, $b);
$d = array_diff_assoc($a, $b);
$e = array_diff_key($a, $b);
echo '<b>$a</b> = ';
var_dump($a);
echo '</br><b>$b</b> = ';
var_dump($b);
echo '</br><h2>array_diff($a, $b) Result</h2>';
var_dump($c);
echo '</br><h2>array_diff_assoc($a, $b) Result</h2>';
var_dump($d);
echo '</br><h2>array_diff_key($a, $b) Result</h2>';
var_dump($e );
?>

Output:

$a = array (size=3)
  'z' => int 1
  'a' => int 5
  'e' => string '7' (length=1)

$b = array (size=3)
  'a' => int 5
  'g' => int 3
  'z' => int 7

array_diff($a, $b) Result:

array (size=1)
  'z' => int 1

array_diff_assoc($a, $b) Result:

array (size=2)
  'z' => int 1
  'e' => string '7' (length=1)

array_diff_key($a, $b) Result:

array (size=1)
  'e' => string '7' (length=1)