Introduction
In this article I explain the PHP array functions array_diff_assoc, array_diff_key and array_diff_uassoc. To learn some other math functions, go to:
- Array Functions in PHP: PART 1
- Array Functions in PHP: PART 2
PHP array_diff_assoc Function
The array_diff_assoc function compares two or more arrays and returns an array containing all values from array1 that are not present in the other array(s).
Syntax
array_diff_assoc(array1,array2,array3...........) |
Parameter in array_diff_assoc Function
The parameters for the array_diff_assoc function are:
Parameter |
Description |
array1 |
It specifies an array that is compared to the others. |
array2 |
It specifies an array to compare against. |
.................. |
It specifies zero or more arrays to compare against. |
Example of array_diff_assoc Function
The following example creates two arrays and compares them:
<?php
$array1=array("a" => "Apple", "b" => "Mango", "c" => "Orange", "Banana");
$array2 = array("a" => "Apple", "Raspberry", "banana");
echo "<pre>";
$result = array_diff_assoc($array1, $array2);
print_r($result);
?>
Output
PHP array_diff_key Function
The array_diff_key function compares the keys of two or more arrays and returns an array of all values from array1 whose keys are not in any other of array(s).
Syntax
array_diff_key(array1,array2,array3...........) |
Parameter in array_diff_key Function
The parameters for the array_diff_key function are:
Parameter |
Description |
array1 |
It specifies an array that is compared to the others. |
array2 |
It specifies an array to compare against. |
.................. |
It specifies zero or more arrays to compare against. |
Example of array_diff_key Function
The following example creates two arrays and compares their keys:
<?php
$array1=array("a" => "Apple", "b" => "Mango", "c" => "Orange", "Banana");
$array2 = array("a" => "Apple", "b"=>"Raspberry", "banana");
echo "<pre>";
$result = array_diff_key($array1, $array2);
print_r($result);
?>
Output
PHP array_diff_uassoc Function
The array_diff_uassoc function checks the differences of array keys using a user defined function and returns an array containing all the entries from array1 that are not present in any of the other arrays.
Syntax
array_diff_uassoc(array1,array2,array3...........userDefined function) |
Parameter in array_diff_uassoc Function
The parameters for the array_diff_uassoc function are:
Parameter |
Description |
array1 |
It specifies an array that is compared to the others. |
array2 |
It specifies an array to compare against. |
.................. |
It specifies zero or more arrays to compare against. |
userDefined function |
It specifies the name of the user defined function. |
Example of array_diff_uassoc Function
The following example creates two arrays and compares the keys using the user defined function "myfunction":
<?php
functionmyfunction($array1,$array2)
{
if ($array1===$array2)
{
return 0;
}
if ($array1>$array2)
{
return 1;
}
else
{
return -1;
}
}
$array1 = array("a" => "Apple", "b" => "Mango", "c" => "Orange", "Banana");
$array2 = array("a" => "Apple", "b"=>"Raspberry", "banana");
echo "<pre>";
$result = array_diff_uassoc($array1, $array2, "myfunction");
print_r($result);
?>
Output