array_intersect_assoc : intersection of two or more arrays with additional index check

array_intersect_assoc(): common key/value pairs

array_intersect_assoc() keeps entries from the first array whose key and value both match entries in all comparison arrays.

$first = ['a' => 'red', 'b' => 'green'];
$second = ['a' => 'red', 'b' => 'blue'];
$result = array_intersect_assoc($first, $second);
print_r($result);

A matching value under a different key is not considered the same entry.

This function takes two or more arrays as input and then returns the associative array containing all the values in input array ( $array1) that are present in all of the arguments.

$new_array = array_intersect_assoc ($array1, $array2,....);

$array1 : Required , the input array which will be checked.
$array2 : Required , the value and key to be matched with $array1.

Here keys are also used for comparison in addition to values. ( In array_intersect() only values are used for comparison )

Example with two arrays

$first=array('One' =>1,'Two'=>2,'Three'=>3,'Four'=>'Fourth');
$second=array('One'=>1,'Two'=>2,'Third'=>3);

$result1=array_intersect_assoc($first,$second);
foreach ($result1 as $key => $val) {
echo "$key -> $val <br>";
}

Output is here.

One -> 1 
Two -> 2

Keys of the first index are retained. ( no re-indexing done here) . The third element is not included as the key is different in both arrays.

Example with three arrays

$first=array('One' =>1,'Two'=>2,'Three'=>3,'Four'=>'Fourth');
$second=array('One'=>1,'Two'=>2,'Third'=>3);
$third=array('One'=>1);
$result1=array_intersect_assoc($first,$second,$third);
foreach ($result1 as $key => $val) {
echo "$key -> $val <br>";
}

Output is here.

One -> 1

Example: Case-Insensitive Key Comparison

$array1 = ["A" => "apple", "b" => "banana"];
$array2 = ["a" => "apple", "B" => "banana"];
$result = array_intersect_uassoc($array1, $array2, 'strcasecmp');
print_r($result);
// Output: Array ( [A] => apple [b] => banana )

Difference between arrays considering values
Array REFERENCE

Subhendu Mohapatra

Author & Instructor at plus2net

I write and maintain practical tutorials on Python, PHP, SQL, JavaScript, HTML, jQuery, and web development at plus2net. The tutorials focus on clear explanations, working examples, and code that readers can test and adapt while learning.

About the author Watch on YouTube

Connect:

Subscribe to our YouTube Channel here

array_intersect_assoc(): Intersection of two or more arrays

array_intersect_assoc(): common key/value pairs

Example with two arrays

Example with three arrays

Example: Case-Insensitive Key Comparison

Subhendu Mohapatra