PHP array_udiff_uassoc() Function

The PHP array_udiff_uassoc() function compares keys and values of an array against one or more other arrays and returns all elements of the first array that are not present in any of the other arrays. This function compares keys and values using two user-defined comparison functions.

Syntax

array_udiff_uassoc(array, arrays, myfunc_value, myfunc_key)

Parameters

`array`	`Required.` Specify an array to compare from.
`arrays`	`Required.` Specify one or more arrays to compare against.
`myfunc_value`	`Required.` Specify user-defined function to compare values. The comparison function must return an integer <, =, or > than 0 if the first argument is <, =, or > than the second argument.
`myfunc_key`	`Required.` Specify user-defined function to compare keys. The comparison function must return an integer <, =, or > than 0 if the first argument is <, =, or > than the second argument.

Return Value

Returns an array containing all the entries from array which are not present in any of the other arrays.

Exceptions

NA.

Example:

The example below shows the usage of array_udiff_uassoc() function.

<?php
function MyFunc_Value($x, $y) {
  if ($x == $y) 
    return 0;
  return ($x < $y)? -1: 1;
}

function MyFunc_Key($x, $y) {
  if ($x == $y) 
    return 0;
  return ($x < $y)? -1: 1;
}

$Arr1 = array(0, 1, 2, 3);
$Arr2 = array(1, 0, 2, 3);

//comparing Arr1 against Arr2
$Arr1_diff_Arr2 = array_udiff_uassoc($Arr1, $Arr2, 
                      'MyFunc_Value', 'MyFunc_Key');
print_r($Arr1_diff_Arr2);
?>

The output of the above code will be:

Array
(
    [0] => 0
    [1] => 1
)

Example:

Consider one more example which illustrates on usage of array_udiff_uassoc() function.

<?php
function MyFunc_Value($x, $y) {
  if ($x == $y) 
    return 0;
  return ($x < $y)? -1: 1;
}

function MyFunc_Key($x, $y) {
  if ($x == $y) 
    return 0;
  return ($x < $y)? -1: 1;
}

$Arr1 = array("a"=>"Red", 
              "b"=>"Blue",
              "c"=>"Green");
$Arr2 = array("a"=>"Red", "Blue", "Green");

//comparing Arr1 against Arr2
$Arr1_diff_Arr2 = array_udiff_uassoc($Arr1, $Arr2, 
                      'MyFunc_Value', 'MyFunc_Key');
print_r($Arr1_diff_Arr2);
?>

The output of the above code will be:

Array
(
    [b] => Blue
    [c] => Green
)

❮ PHP Array Reference